diff --git a/packages/docs/content/docs/providers.mdx b/packages/docs/content/docs/providers.mdx
index 3ca47e22..10f97be2 100644
--- a/packages/docs/content/docs/providers.mdx
+++ b/packages/docs/content/docs/providers.mdx
@@ -10,11 +10,20 @@ Before OpenChamber can do anything, it needs at least one AI provider connected.
 ## Connect a provider
 
 1. Open **Settings → Providers**.
-2. Open the **Add provider** menu and pick a provider that isn't connected yet.
+2. Open the **Add provider** menu and pick a provider that isn't connected yet, or choose **Other / Custom** for an OpenAI-compatible endpoint.
 3. Sign in one of two ways, depending on the provider:
    - **API key** — paste your key and save.
    - **Sign-in (device flow)** — OpenChamber shows a link and a short code. Open the link, enter the code, and approve. OpenChamber finishes connecting on its own.
 
+### Custom / Other providers
+
+For gateways, campus LLMs, Ollama, LiteLLM, and similar OpenAI-compatible APIs:
+
+1. Choose **Other / Custom** in the provider list.
+2. Enter a provider ID, display name, base URL (`http://` or `https://`), API key (or `{env:VAR_NAME}`), and at least one model id/name.
+3. Optionally add request headers.
+4. Save — OpenChamber writes the provider block to OpenCode config and stores the key in OpenCode auth.
+
 When a provider shows as connected, its models become available in chat.
 
 To disconnect, open the provider and choose to remove its sign-in.
diff --git a/packages/ui/src/components/sections/providers/CustomProviderForm.tsx b/packages/ui/src/components/sections/providers/CustomProviderForm.tsx
new file mode 100644
index 00000000..96aa7003
--- /dev/null
+++ b/packages/ui/src/components/sections/providers/CustomProviderForm.tsx
@@ -0,0 +1,335 @@
+import React from 'react';
+import {
+  SettingsSection,
+  SettingsStackedField,
+  SETTINGS_FIELDS_STACK_CLASS,
+  SETTINGS_FIELD_LABEL_CLASS,
+  SETTINGS_HELPER_CLASS,
+  SETTINGS_ICON_BUTTON_CLASS,
+  SETTINGS_CONTROL_CLUSTER_CLASS,
+} from '@/components/sections/shared/SettingsSection';
+import { Button } from '@/components/ui/button';
+import { Input } from '@/components/ui/input';
+import { Icon } from '@/components/icon/Icon';
+import { useI18n } from '@/lib/i18n';
+import {
+  createEmptyCustomProviderForm,
+  createHeaderRow,
+  createModelRow,
+  validateCustomProvider,
+  type CustomProviderFormState,
+  type CustomProviderPersistPlan,
+  type CustomProviderTranslator,
+  type FieldErrors,
+  type HeaderFieldErrors,
+  type ModelFieldErrors,
+} from './custom-provider-form';
+
+type CustomProviderFormProps = {
+  existingProviderIDs: ReadonlySet<string>;
+  disabledProviders?: readonly string[];
+  busy?: boolean;
+  onSubmit: (plan: CustomProviderPersistPlan) => void | Promise<void>;
+  onCancel?: () => void;
+};
+
+export const CustomProviderForm: React.FC<CustomProviderFormProps> = ({
+  existingProviderIDs,
+  disabledProviders = [],
+  busy = false,
+  onSubmit,
+  onCancel,
+}) => {
+  const { t } = useI18n();
+  const [form, setForm] = React.useState<CustomProviderFormState>(() => createEmptyCustomProviderForm());
+  const [err, setErr] = React.useState<FieldErrors>({});
+  const [modelErrors, setModelErrors] = React.useState<ModelFieldErrors[]>([]);
+  const [headerErrors, setHeaderErrors] = React.useState<HeaderFieldErrors[]>([]);
+
+  const setField = (key: keyof Pick<CustomProviderFormState, 'providerID' | 'name' | 'baseURL' | 'apiKey'>, value: string) => {
+    setForm((prev) => ({ ...prev, [key]: value }));
+    if (key !== 'apiKey') {
+      setErr((prev) => ({ ...prev, [key]: undefined }));
+    }
+  };
+
+  const setModel = (index: number, key: 'id' | 'name', value: string) => {
+    setForm((prev) => ({
+      ...prev,
+      models: prev.models.map((row, rowIndex) => (rowIndex === index ? { ...row, [key]: value } : row)),
+    }));
+    setModelErrors((prev) => {
+      const next = [...prev];
+      next[index] = { ...(next[index] ?? {}), [key]: undefined };
+      return next;
+    });
+  };
+
+  const setHeader = (index: number, key: 'key' | 'value', value: string) => {
+    setForm((prev) => ({
+      ...prev,
+      headers: prev.headers.map((row, rowIndex) => (rowIndex === index ? { ...row, [key]: value } : row)),
+    }));
+    setHeaderErrors((prev) => {
+      const next = [...prev];
+      next[index] = { ...(next[index] ?? {}), [key]: undefined };
+      return next;
+    });
+  };
+
+  const handleSubmit = async (event: React.FormEvent) => {
+    event.preventDefault();
+    if (busy) {
+      return;
+    }
+
+    const output = validateCustomProvider({
+      form,
+      t: ((key, vars) => t(key as Parameters<typeof t>[0], vars)) as CustomProviderTranslator,
+      existingProviderIDs,
+      disabledProviders,
+    });
+    setErr(output.err);
+    setModelErrors(output.models);
+    setHeaderErrors(output.headers);
+    if (!output.result) {
+      return;
+    }
+    await onSubmit(output.result);
+  };
+
+  return (
+    <form onSubmit={handleSubmit} className="space-y-0">
+      <SettingsSection
+        title={t('settings.providers.page.custom.title')}
+        divider={false}
+        settingsItem="providers.custom"
+        contentClassName={SETTINGS_FIELDS_STACK_CLASS}
+      >
+        <p className={SETTINGS_HELPER_CLASS}>{t('settings.providers.page.custom.description')}</p>
+
+        <SettingsStackedField
+          label={t('settings.providers.page.custom.field.providerID.label')}
+          info={t('settings.providers.page.custom.field.providerID.info')}
+        >
+          <Input
+            value={form.providerID}
+            onChange={(event) => setField('providerID', event.target.value)}
+            placeholder={t('settings.providers.page.custom.field.providerID.placeholder')}
+            className="h-8 rounded-md px-3 font-mono text-xs"
+            autoFocus
+            aria-invalid={Boolean(err.providerID)}
+            aria-label={t('settings.providers.page.custom.field.providerID.label')}
+          />
+          {err.providerID ? <p className="mt-1 typography-meta text-[var(--status-error)]">{err.providerID}</p> : null}
+        </SettingsStackedField>
+
+        <SettingsStackedField
+          label={t('settings.providers.page.custom.field.name.label')}
+          info={t('settings.providers.page.custom.field.name.info')}
+        >
+          <Input
+            value={form.name}
+            onChange={(event) => setField('name', event.target.value)}
+            placeholder={t('settings.providers.page.custom.field.name.placeholder')}
+            className="h-8 rounded-md px-3"
+            aria-invalid={Boolean(err.name)}
+            aria-label={t('settings.providers.page.custom.field.name.label')}
+          />
+          {err.name ? <p className="mt-1 typography-meta text-[var(--status-error)]">{err.name}</p> : null}
+        </SettingsStackedField>
+
+        <SettingsStackedField
+          label={t('settings.providers.page.custom.field.baseURL.label')}
+          info={t('settings.providers.page.custom.field.baseURL.info')}
+        >
+          <Input
+            value={form.baseURL}
+            onChange={(event) => setField('baseURL', event.target.value)}
+            placeholder={t('settings.providers.page.custom.field.baseURL.placeholder')}
+            className="h-8 rounded-md px-3 font-mono text-xs"
+            aria-invalid={Boolean(err.baseURL)}
+            aria-label={t('settings.providers.page.custom.field.baseURL.label')}
+          />
+          {err.baseURL ? <p className="mt-1 typography-meta text-[var(--status-error)]">{err.baseURL}</p> : null}
+        </SettingsStackedField>
+
+        <SettingsStackedField
+          label={t('settings.providers.page.custom.field.apiKey.label')}
+          info={t('settings.providers.page.custom.field.apiKey.info')}
+        >
+          <Input
+            type="password"
+            value={form.apiKey}
+            onChange={(event) => setField('apiKey', event.target.value)}
+            placeholder={t('settings.providers.page.custom.field.apiKey.placeholder')}
+            className="h-8 rounded-md px-3 font-mono text-xs"
+            aria-label={t('settings.providers.page.custom.field.apiKey.label')}
+          />
+        </SettingsStackedField>
+      </SettingsSection>
+
+      <SettingsSection
+        title={t('settings.providers.page.custom.models.title')}
+        contentClassName={SETTINGS_FIELDS_STACK_CLASS}
+      >
+        {form.models.map((model, index) => (
+          <div key={model.row} className={`${SETTINGS_CONTROL_CLUSTER_CLASS} space-y-2`}>
+            <div className="flex items-start gap-2">
+              <div className="min-w-0 flex-1 space-y-2">
+                <div>
+                  <label className={SETTINGS_FIELD_LABEL_CLASS}>
+                    {t('settings.providers.page.custom.models.idLabel')}
+                  </label>
+                  <Input
+                    value={model.id}
+                    onChange={(event) => setModel(index, 'id', event.target.value)}
+                    placeholder={t('settings.providers.page.custom.models.idPlaceholder')}
+                    className="mt-1 h-8 rounded-md px-3 font-mono text-xs"
+                    aria-label={t('settings.providers.page.custom.models.idLabel')}
+                  />
+                  {modelErrors[index]?.id ? (
+                    <p className="mt-1 typography-meta text-[var(--status-error)]">{modelErrors[index]?.id}</p>
+                  ) : null}
+                </div>
+                <div>
+                  <label className={SETTINGS_FIELD_LABEL_CLASS}>
+                    {t('settings.providers.page.custom.models.nameLabel')}
+                  </label>
+                  <Input
+                    value={model.name}
+                    onChange={(event) => setModel(index, 'name', event.target.value)}
+                    placeholder={t('settings.providers.page.custom.models.namePlaceholder')}
+                    className="mt-1 h-8 rounded-md px-3"
+                    aria-label={t('settings.providers.page.custom.models.nameLabel')}
+                  />
+                  {modelErrors[index]?.name ? (
+                    <p className="mt-1 typography-meta text-[var(--status-error)]">{modelErrors[index]?.name}</p>
+                  ) : null}
+                </div>
+              </div>
+              <Button
+                type="button"
+                variant="ghost"
+                size="icon"
+                className={SETTINGS_ICON_BUTTON_CLASS}
+                disabled={form.models.length <= 1}
+                onClick={() => {
+                  if (form.models.length <= 1) return;
+                  setForm((prev) => ({
+                    ...prev,
+                    models: prev.models.filter((_, rowIndex) => rowIndex !== index),
+                  }));
+                  setModelErrors((prev) => prev.filter((_, rowIndex) => rowIndex !== index));
+                }}
+                aria-label={t('settings.providers.page.custom.models.remove')}
+              >
+                <Icon name="delete-bin" className="size-4" />
+              </Button>
+            </div>
+          </div>
+        ))}
+        <Button
+          type="button"
+          variant="outline"
+          size="xs"
+          className="!font-normal"
+          onClick={() => {
+            setForm((prev) => ({ ...prev, models: [...prev.models, createModelRow()] }));
+            setModelErrors((prev) => [...prev, {}]);
+          }}
+        >
+          {t('settings.providers.page.custom.models.add')}
+        </Button>
+      </SettingsSection>
+
+      <SettingsSection
+        title={t('settings.providers.page.custom.headers.title')}
+        contentClassName={SETTINGS_FIELDS_STACK_CLASS}
+      >
+        <p className={SETTINGS_HELPER_CLASS}>{t('settings.providers.page.custom.headers.description')}</p>
+        {form.headers.map((header, index) => (
+          <div key={header.row} className={`${SETTINGS_CONTROL_CLUSTER_CLASS} space-y-2`}>
+            <div className="flex items-start gap-2">
+              <div className="min-w-0 flex-1 space-y-2">
+                <div>
+                  <label className={SETTINGS_FIELD_LABEL_CLASS}>
+                    {t('settings.providers.page.custom.headers.keyLabel')}
+                  </label>
+                  <Input
+                    value={header.key}
+                    onChange={(event) => setHeader(index, 'key', event.target.value)}
+                    placeholder={t('settings.providers.page.custom.headers.keyPlaceholder')}
+                    className="mt-1 h-8 rounded-md px-3 font-mono text-xs"
+                    aria-label={t('settings.providers.page.custom.headers.keyLabel')}
+                  />
+                  {headerErrors[index]?.key ? (
+                    <p className="mt-1 typography-meta text-[var(--status-error)]">{headerErrors[index]?.key}</p>
+                  ) : null}
+                </div>
+                <div>
+                  <label className={SETTINGS_FIELD_LABEL_CLASS}>
+                    {t('settings.providers.page.custom.headers.valueLabel')}
+                  </label>
+                  <Input
+                    value={header.value}
+                    onChange={(event) => setHeader(index, 'value', event.target.value)}
+                    placeholder={t('settings.providers.page.custom.headers.valuePlaceholder')}
+                    className="mt-1 h-8 rounded-md px-3 font-mono text-xs"
+                    aria-label={t('settings.providers.page.custom.headers.valueLabel')}
+                  />
+                  {headerErrors[index]?.value ? (
+                    <p className="mt-1 typography-meta text-[var(--status-error)]">{headerErrors[index]?.value}</p>
+                  ) : null}
+                </div>
+              </div>
+              <Button
+                type="button"
+                variant="ghost"
+                size="icon"
+                className={SETTINGS_ICON_BUTTON_CLASS}
+                disabled={form.headers.length <= 1}
+                onClick={() => {
+                  if (form.headers.length <= 1) return;
+                  setForm((prev) => ({
+                    ...prev,
+                    headers: prev.headers.filter((_, rowIndex) => rowIndex !== index),
+                  }));
+                  setHeaderErrors((prev) => prev.filter((_, rowIndex) => rowIndex !== index));
+                }}
+                aria-label={t('settings.providers.page.custom.headers.remove')}
+              >
+                <Icon name="delete-bin" className="size-4" />
+              </Button>
+            </div>
+          </div>
+        ))}
+        <Button
+          type="button"
+          variant="outline"
+          size="xs"
+          className="!font-normal"
+          onClick={() => {
+            setForm((prev) => ({ ...prev, headers: [...prev.headers, createHeaderRow()] }));
+            setHeaderErrors((prev) => [...prev, {}]);
+          }}
+        >
+          {t('settings.providers.page.custom.headers.add')}
+        </Button>
+      </SettingsSection>
+
+      <div className="flex flex-wrap items-center gap-2 py-4">
+        {onCancel ? (
+          <Button type="button" variant="outline" size="xs" className="!font-normal" onClick={onCancel} disabled={busy}>
+            {t('settings.providers.page.custom.actions.back')}
+          </Button>
+        ) : null}
+        <Button type="submit" size="xs" className="!font-normal" disabled={busy}>
+          {busy
+            ? t('settings.providers.page.actions.saving')
+            : t('settings.providers.page.custom.actions.save')}
+        </Button>
+      </div>
+    </form>
+  );
+};
diff --git a/packages/ui/src/components/sections/providers/ProvidersPage.tsx b/packages/ui/src/components/sections/providers/ProvidersPage.tsx
index 3dd15fd8..5c1f8df6 100644
--- a/packages/ui/src/components/sections/providers/ProvidersPage.tsx
+++ b/packages/ui/src/components/sections/providers/ProvidersPage.tsx
@@ -26,6 +26,13 @@ import { getCurrentIntlLocale, useI18n } from '@/lib/i18n';
 import { runtimeFetch } from '@/lib/runtime-fetch';
 import { opencodeClient } from '@/lib/opencode/client';
 import { shouldLoadAvailableProviders } from './providerAvailability';
+import { CustomProviderForm } from './CustomProviderForm';
+import {
+  buildAuthSetRequest,
+  buildProviderUpsertRequest,
+  CUSTOM_PROVIDER_ID,
+  type CustomProviderPersistPlan,
+} from './custom-provider-form';
 
 const formatCompactNumber = (value: number) => new Intl.NumberFormat(getCurrentIntlLocale(), {
   notation: 'compact',
@@ -173,6 +180,7 @@ export const ProvidersPage: React.FC = () => {
   const [providerSources, setProviderSources] = React.useState<Record<string, ProviderSources>>({});
   const [showAuthPanel, setShowAuthPanel] = React.useState(false);
   const isAddMode = selectedProviderId === ADD_PROVIDER_ID;
+  const isCustomMode = isAddMode && candidateProviderId === CUSTOM_PROVIDER_ID;
 
   React.useEffect(() => {
     if (!selectedProviderId && providers.length > 0) {
@@ -271,7 +279,11 @@ export const ProvidersPage: React.FC = () => {
       return;
     }
 
-    if (candidateProviderId && !unconnectedProviders.some((provider) => provider.id === candidateProviderId)) {
+    if (
+      candidateProviderId
+      && candidateProviderId !== CUSTOM_PROVIDER_ID
+      && !unconnectedProviders.some((provider) => provider.id === candidateProviderId)
+    ) {
       setCandidateProviderId('');
     }
   }, [selectedProviderId, candidateProviderId, unconnectedProviders]);
@@ -361,6 +373,49 @@ export const ProvidersPage: React.FC = () => {
     }
   };
 
+  const handleSaveCustomProvider = async (plan: CustomProviderPersistPlan) => {
+    const busyKey = `custom:${plan.providerID}`;
+    setAuthBusyKey(busyKey);
+
+    try {
+      const upsertBody = buildProviderUpsertRequest(plan);
+      const response = await runtimeFetch('/api/provider', {
+        method: 'PUT',
+        headers: {
+          Accept: 'application/json',
+          'Content-Type': 'application/json',
+        },
+        body: JSON.stringify(upsertBody),
+      });
+      const payload = await response.json().catch(() => null);
+      if (!response.ok) {
+        throw new Error(payload?.error || t('settings.providers.page.toast.customProviderSaveFailed'));
+      }
+
+      const authRequest = buildAuthSetRequest(plan);
+      if (authRequest) {
+        const authResult = await opencodeClient.getSdkClient().auth.set(authRequest);
+        if (authResult.error) {
+          throw new Error(t('settings.providers.page.toast.apiKeySaveFailed'));
+        }
+      }
+
+      toast.success(t('settings.providers.page.toast.customProviderSaved', { provider: plan.name }));
+      setCandidateProviderId('');
+      await reloadOpenCodeConfiguration({ scopes: ['providers'], mode: 'active' });
+      setSelectedProvider(plan.providerID);
+    } catch (error) {
+      console.error('Failed to save custom provider:', error);
+      toast.error(
+        error instanceof Error && error.message
+          ? error.message
+          : t('settings.providers.page.toast.customProviderSaveFailed'),
+      );
+    } finally {
+      setAuthBusyKey(null);
+    }
+  };
+
   const handleOAuthStart = async (providerId: string, methodIndex: number) => {
     const busyKey = `oauth:${providerId}:${methodIndex}`;
     setAuthBusyKey(busyKey);
@@ -528,8 +583,6 @@ export const ProvidersPage: React.FC = () => {
                     <p className="typography-meta text-muted-foreground">{t('settings.providers.page.state.loading')}</p>
                   ) : availableError ? (
                     <p className="typography-meta text-muted-foreground">{availableError}</p>
-                  ) : unconnectedProviders.length === 0 ? (
-                    <p className="typography-meta text-muted-foreground">{t('settings.providers.page.connect.allProvidersConnected')}</p>
                   ) : (
                     <DropdownMenu open={providerDropdownOpen} onOpenChange={(open) => {
                       setProviderDropdownOpen(open);
@@ -541,11 +594,15 @@ export const ProvidersPage: React.FC = () => {
                           className={SETTINGS_CUSTOM_TRIGGER_CLASS}
                         >
                           <span className="flex items-center gap-2 min-w-0">
-                            {candidateProviderId ? <ProviderLogo providerId={candidateProviderId} className="h-3.5 w-3.5 flex-shrink-0" /> : null}
+                            {candidateProviderId && candidateProviderId !== CUSTOM_PROVIDER_ID ? (
+                              <ProviderLogo providerId={candidateProviderId} className="h-3.5 w-3.5 flex-shrink-0" />
+                            ) : null}
                             <span className={cn("truncate typography-ui-label font-normal", candidateProviderId ? "text-foreground" : "text-muted-foreground")}>
-                              {candidateProviderId
-                                ? (unconnectedProviders.find(p => p.id === candidateProviderId)?.name || candidateProviderId)
-                                : t('settings.providers.page.connect.selectProviderPlaceholder')}
+                              {candidateProviderId === CUSTOM_PROVIDER_ID
+                                ? t('settings.providers.page.custom.optionLabel')
+                                : candidateProviderId
+                                  ? (unconnectedProviders.find(p => p.id === candidateProviderId)?.name || candidateProviderId)
+                                  : t('settings.providers.page.connect.selectProviderPlaceholder')}
                             </span>
                           </span>
                           <Icon name="arrow-down-s" className="h-4 w-4 flex-shrink-0 text-muted-foreground/50" />
@@ -573,32 +630,60 @@ export const ProvidersPage: React.FC = () => {
                         </div>
                         <ScrollableOverlay outerClassName="max-h-[240px]" className="p-1">
                           {(() => {
+                            const query = providerSearchQuery.toLowerCase();
+                            const customLabel = t('settings.providers.page.custom.optionLabel');
+                            const customMatches = !query
+                              || customLabel.toLowerCase().includes(query)
+                              || 'other'.includes(query)
+                              || 'custom'.includes(query);
                             const filtered = unconnectedProviders.filter(p => {
-                              const query = providerSearchQuery.toLowerCase();
                               return (p.name || p.id).toLowerCase().includes(query) || p.id.toLowerCase().includes(query);
                             });
-                            if (filtered.length === 0) {
+                            if (filtered.length === 0 && !customMatches) {
                               return <p className="py-4 text-center typography-meta text-muted-foreground">{t('settings.providers.page.connect.noProvidersFound')}</p>;
                             }
-                            return filtered.map((provider) => (
-                              <DropdownMenuItem
-                                key={provider.id}
-                                onSelect={() => {
-                                  setCandidateProviderId(provider.id);
-                                  setProviderDropdownOpen(false);
-                                  setProviderSearchQuery('');
-                                }}
-                                className="flex items-center justify-between"
-                              >
-                                <span className="flex items-center gap-2 min-w-0">
-                                  <ProviderLogo providerId={provider.id} className="h-4 w-4 flex-shrink-0" />
-                                  <span className="truncate">{provider.name || provider.id}</span>
-                                </span>
-                                {candidateProviderId === provider.id && (
-                                  <Icon name="check" className="h-4 w-4 text-[var(--primary-base)]" />
-                                )}
-                              </DropdownMenuItem>
-                            ));
+                            return (
+                              <>
+                                {filtered.map((provider) => (
+                                  <DropdownMenuItem
+                                    key={provider.id}
+                                    onSelect={() => {
+                                      setCandidateProviderId(provider.id);
+                                      setProviderDropdownOpen(false);
+                                      setProviderSearchQuery('');
+                                    }}
+                                    className="flex items-center justify-between"
+                                  >
+                                    <span className="flex items-center gap-2 min-w-0">
+                                      <ProviderLogo providerId={provider.id} className="h-4 w-4 flex-shrink-0" />
+                                      <span className="truncate">{provider.name || provider.id}</span>
+                                    </span>
+                                    {candidateProviderId === provider.id && (
+                                      <Icon name="check" className="h-4 w-4 text-[var(--primary-base)]" />
+                                    )}
+                                  </DropdownMenuItem>
+                                ))}
+                                {customMatches ? (
+                                  <DropdownMenuItem
+                                    key={CUSTOM_PROVIDER_ID}
+                                    onSelect={() => {
+                                      setCandidateProviderId(CUSTOM_PROVIDER_ID);
+                                      setProviderDropdownOpen(false);
+                                      setProviderSearchQuery('');
+                                    }}
+                                    className="flex items-center justify-between"
+                                  >
+                                    <span className="flex items-center gap-2 min-w-0">
+                                      <Icon name="add" className="h-4 w-4 flex-shrink-0" />
+                                      <span className="truncate">{customLabel}</span>
+                                    </span>
+                                    {candidateProviderId === CUSTOM_PROVIDER_ID && (
+                                      <Icon name="check" className="h-4 w-4 text-[var(--primary-base)]" />
+                                    )}
+                                  </DropdownMenuItem>
+                                ) : null}
+                              </>
+                            );
                           })()}
                         </ScrollableOverlay>
                       </DropdownMenuContent>
@@ -607,7 +692,14 @@ export const ProvidersPage: React.FC = () => {
               </div>
         </SettingsSection>
 
-          {candidateProviderId && (
+          {isCustomMode ? (
+            <CustomProviderForm
+              existingProviderIDs={connectedProviderIds}
+              busy={authBusyKey?.startsWith('custom:') ?? false}
+              onCancel={() => setCandidateProviderId('')}
+              onSubmit={handleSaveCustomProvider}
+            />
+          ) : candidateProviderId ? (
             <SettingsSection
               title={t('settings.providers.page.auth.title')}
               settingsItem="providers.auth"
@@ -741,7 +833,7 @@ export const ProvidersPage: React.FC = () => {
                 </>
               )}
             </SettingsSection>
-          )}
+          ) : null}
       </SettingsPageLayout>
     );
   }
diff --git a/packages/ui/src/components/sections/providers/custom-provider-form.test.ts b/packages/ui/src/components/sections/providers/custom-provider-form.test.ts
new file mode 100644
index 00000000..438dea05
--- /dev/null
+++ b/packages/ui/src/components/sections/providers/custom-provider-form.test.ts
@@ -0,0 +1,202 @@
+import { describe, expect, test } from 'bun:test';
+import {
+  buildAuthSetRequest,
+  buildProviderUpsertRequest,
+  mergeProviderConfig,
+  validateCustomProvider,
+  type CustomProviderFormState,
+} from './custom-provider-form';
+
+const t = (key: string) => key;
+
+const baseForm = (overrides: Partial<CustomProviderFormState> = {}): CustomProviderFormState => ({
+  providerID: 'custom-provider',
+  name: 'Custom Provider',
+  baseURL: 'https://api.example.com/v1',
+  apiKey: 'sk-test',
+  models: [{ row: 'm0', id: 'model-a', name: 'Model A' }],
+  headers: [{ row: 'h0', key: '', value: '' }],
+  ...overrides,
+});
+
+describe('validateCustomProvider', () => {
+  test('builds trimmed config and auth payloads', () => {
+    const result = validateCustomProvider({
+      form: baseForm({
+        providerID: ' custom-provider ',
+        name: ' Custom Provider ',
+        baseURL: ' https://api.example.com/v1 ',
+        apiKey: ' sk-secret ',
+        models: [{ row: 'm0', id: ' model-a ', name: ' Model A ' }],
+        headers: [
+          { row: 'h0', key: ' X-Test ', value: ' enabled ' },
+          { row: 'h1', key: '', value: '' },
+        ],
+      }),
+      t,
+      existingProviderIDs: new Set(),
+    });
+
+    expect(result.result).toEqual({
+      providerID: 'custom-provider',
+      name: 'Custom Provider',
+      apiKey: 'sk-secret',
+      config: {
+        npm: '@ai-sdk/openai-compatible',
+        name: 'Custom Provider',
+        options: {
+          baseURL: 'https://api.example.com/v1',
+          headers: {
+            'X-Test': 'enabled',
+          },
+        },
+        models: {
+          'model-a': { name: 'Model A' },
+        },
+      },
+    });
+  });
+
+  test('supports {env:VAR} credentials without writing an auth key', () => {
+    const result = validateCustomProvider({
+      form: baseForm({
+        apiKey: '{env: CUSTOM_PROVIDER_KEY}',
+      }),
+      t,
+      existingProviderIDs: new Set(),
+    });
+
+    expect(result.result?.apiKey).toEqual(undefined);
+    expect(result.result?.config.env).toEqual(['CUSTOM_PROVIDER_KEY']);
+  });
+
+  test('rejects invalid provider id, base URL, and duplicate rows', () => {
+    const result = validateCustomProvider({
+      form: baseForm({
+        providerID: 'Bad ID',
+        baseURL: 'ftp://example.com',
+        models: [
+          { row: 'm0', id: 'model-a', name: 'Model A' },
+          { row: 'm1', id: 'model-a', name: 'Model A 2' },
+        ],
+        headers: [
+          { row: 'h0', key: 'Authorization', value: 'one' },
+          { row: 'h1', key: 'authorization', value: 'two' },
+        ],
+      }),
+      t,
+      existingProviderIDs: new Set(),
+    });
+
+    expect(result.result).toEqual(undefined);
+    expect(result.err.providerID).toBe('settings.providers.page.custom.error.providerID.format');
+    expect(result.err.baseURL).toBe('settings.providers.page.custom.error.baseURL.format');
+    expect(result.models[1]).toEqual({
+      id: 'settings.providers.page.custom.error.duplicate',
+      name: undefined,
+    });
+    expect(result.headers[1]).toEqual({
+      key: 'settings.providers.page.custom.error.duplicate',
+      value: undefined,
+    });
+  });
+
+  test('allows reconnecting a disabled provider id', () => {
+    const result = validateCustomProvider({
+      form: baseForm(),
+      t,
+      existingProviderIDs: new Set(['custom-provider']),
+      disabledProviders: ['custom-provider'],
+    });
+
+    expect(result.result?.providerID).toBe('custom-provider');
+    expect(result.err.providerID).toEqual(undefined);
+  });
+
+  test('rejects an already-connected provider id', () => {
+    const result = validateCustomProvider({
+      form: baseForm(),
+      t,
+      existingProviderIDs: new Set(['custom-provider']),
+    });
+
+    expect(result.result).toEqual(undefined);
+    expect(result.err.providerID).toBe('settings.providers.page.custom.error.providerID.exists');
+  });
+});
+
+describe('request construction', () => {
+  test('builds auth.set and provider upsert requests', () => {
+    const validated = validateCustomProvider({
+      form: baseForm(),
+      t,
+      existingProviderIDs: new Set(),
+    });
+    const plan = validated.result!;
+
+    expect(buildAuthSetRequest(plan)).toEqual({
+      providerID: 'custom-provider',
+      auth: { type: 'api', key: 'sk-test' },
+    });
+    expect(buildProviderUpsertRequest(plan)).toEqual({
+      providerID: 'custom-provider',
+      config: plan.config,
+    });
+  });
+
+  test('omits auth.set when using env credentials', () => {
+    const validated = validateCustomProvider({
+      form: baseForm({ apiKey: '{env:MY_KEY}' }),
+      t,
+      existingProviderIDs: new Set(),
+    });
+
+    expect(buildAuthSetRequest(validated.result!)).toBeNull();
+  });
+});
+
+describe('mergeProviderConfig persistence shape', () => {
+  test('merges provider block and clears disabled_providers entry', () => {
+    const validated = validateCustomProvider({
+      form: baseForm(),
+      t,
+      existingProviderIDs: new Set(),
+    });
+    const plan = validated.result!;
+
+    const next = mergeProviderConfig(
+      {
+        model: 'openai/gpt-4o',
+        provider: {
+          openai: { name: 'OpenAI' },
+        },
+        disabled_providers: ['custom-provider', 'other'],
+      },
+      plan.providerID,
+      plan.config,
+    );
+
+    expect(next).toEqual({
+      model: 'openai/gpt-4o',
+      provider: {
+        openai: { name: 'OpenAI' },
+        'custom-provider': plan.config,
+      },
+      disabled_providers: ['other'],
+    });
+  });
+
+  test('creates provider section when missing', () => {
+    const validated = validateCustomProvider({
+      form: baseForm(),
+      t,
+      existingProviderIDs: new Set(),
+    });
+    const plan = validated.result!;
+
+    const next = mergeProviderConfig({}, plan.providerID, plan.config);
+    expect(next.provider).toEqual({
+      'custom-provider': plan.config,
+    });
+  });
+});
diff --git a/packages/ui/src/components/sections/providers/custom-provider-form.ts b/packages/ui/src/components/sections/providers/custom-provider-form.ts
new file mode 100644
index 00000000..888930cd
--- /dev/null
+++ b/packages/ui/src/components/sections/providers/custom-provider-form.ts
@@ -0,0 +1,301 @@
+/**
+ * Custom / Other OpenAI-compatible provider form helpers.
+ * Mirrors OpenCode web UI validation and request construction so a provider
+ * can be defined from Settings without code changes.
+ */
+
+export const CUSTOM_PROVIDER_NPM = '@ai-sdk/openai-compatible';
+export const CUSTOM_PROVIDER_ID = '__custom_provider__';
+export const PROVIDER_ID_PATTERN = /^[a-z0-9][a-z0-9-_]*$/;
+export const BASE_URL_PATTERN = /^https?:\/\//;
+export const ENV_KEY_PATTERN = /^\{env:([^}]+)\}$/;
+
+export type CustomProviderTranslator = (
+  key: string,
+  vars?: Record<string, string | number | boolean>,
+) => string;
+
+export type ModelRow = {
+  row: string;
+  id: string;
+  name: string;
+};
+
+export type HeaderRow = {
+  row: string;
+  key: string;
+  value: string;
+};
+
+export type CustomProviderFormState = {
+  providerID: string;
+  name: string;
+  baseURL: string;
+  apiKey: string;
+  models: ModelRow[];
+  headers: HeaderRow[];
+};
+
+export type FieldErrors = {
+  providerID?: string;
+  name?: string;
+  baseURL?: string;
+};
+
+export type ModelFieldErrors = {
+  id?: string;
+  name?: string;
+};
+
+export type HeaderFieldErrors = {
+  key?: string;
+  value?: string;
+};
+
+export type CustomProviderConfig = {
+  npm: typeof CUSTOM_PROVIDER_NPM;
+  name: string;
+  env?: string[];
+  options: {
+    baseURL: string;
+    headers?: Record<string, string>;
+  };
+  models: Record<string, { name: string }>;
+};
+
+export type CustomProviderPersistPlan = {
+  providerID: string;
+  name: string;
+  /** Literal API key to send via auth.set; omitted when using {env:VAR} or empty. */
+  apiKey?: string;
+  config: CustomProviderConfig;
+};
+
+export type ValidateCustomProviderInput = {
+  form: CustomProviderFormState;
+  t: CustomProviderTranslator;
+  existingProviderIDs: ReadonlySet<string>;
+  disabledProviders?: readonly string[];
+};
+
+export type ValidateCustomProviderResult = {
+  err: FieldErrors;
+  models: ModelFieldErrors[];
+  headers: HeaderFieldErrors[];
+  result?: CustomProviderPersistPlan;
+};
+
+let rowCounter = 0;
+
+const nextRow = (): string => `row-${rowCounter++}`;
+
+export const createModelRow = (): ModelRow => ({
+  row: nextRow(),
+  id: '',
+  name: '',
+});
+
+export const createHeaderRow = (): HeaderRow => ({
+  row: nextRow(),
+  key: '',
+  value: '',
+});
+
+export const createEmptyCustomProviderForm = (): CustomProviderFormState => ({
+  providerID: '',
+  name: '',
+  baseURL: '',
+  apiKey: '',
+  models: [createModelRow()],
+  headers: [createHeaderRow()],
+});
+
+export function parseEnvApiKey(apiKey: string): { env?: string; key?: string } {
+  const trimmed = apiKey.trim();
+  if (!trimmed) {
+    return {};
+  }
+  const envMatch = trimmed.match(ENV_KEY_PATTERN);
+  const env = envMatch?.[1]?.trim();
+  if (env) {
+    return { env };
+  }
+  return { key: trimmed };
+}
+
+/**
+ * Validates form input and builds the auth + OpenCode provider config payloads.
+ */
+export function validateCustomProvider(input: ValidateCustomProviderInput): ValidateCustomProviderResult {
+  const providerID = input.form.providerID.trim();
+  const name = input.form.name.trim();
+  const baseURL = input.form.baseURL.trim();
+  const { env, key } = parseEnvApiKey(input.form.apiKey);
+  const disabledProviders = input.disabledProviders ?? [];
+
+  const idError = !providerID
+    ? input.t('settings.providers.page.custom.error.providerID.required')
+    : !PROVIDER_ID_PATTERN.test(providerID)
+      ? input.t('settings.providers.page.custom.error.providerID.format')
+      : undefined;
+
+  const nameError = !name
+    ? input.t('settings.providers.page.custom.error.name.required')
+    : undefined;
+
+  const urlError = !baseURL
+    ? input.t('settings.providers.page.custom.error.baseURL.required')
+    : !BASE_URL_PATTERN.test(baseURL)
+      ? input.t('settings.providers.page.custom.error.baseURL.format')
+      : undefined;
+
+  const disabled = disabledProviders.includes(providerID);
+  const existsError = idError
+    ? undefined
+    : input.existingProviderIDs.has(providerID) && !disabled
+      ? input.t('settings.providers.page.custom.error.providerID.exists')
+      : undefined;
+
+  const seenModels = new Set<string>();
+  const modelErrors = input.form.models.map((model) => {
+    const id = model.id.trim();
+    const modelIdError = !id
+      ? input.t('settings.providers.page.custom.error.required')
+      : seenModels.has(id)
+        ? input.t('settings.providers.page.custom.error.duplicate')
+        : (() => {
+            seenModels.add(id);
+            return undefined;
+          })();
+    const modelNameError = !model.name.trim()
+      ? input.t('settings.providers.page.custom.error.required')
+      : undefined;
+    return { id: modelIdError, name: modelNameError };
+  });
+
+  const modelsValid = modelErrors.every((entry) => !entry.id && !entry.name);
+  const modelConfig = Object.fromEntries(
+    input.form.models.map((model) => [model.id.trim(), { name: model.name.trim() }]),
+  );
+
+  const seenHeaders = new Set<string>();
+  const headerErrors = input.form.headers.map((header) => {
+    const headerKey = header.key.trim();
+    const headerValue = header.value.trim();
+    if (!headerKey && !headerValue) {
+      return {};
+    }
+    const keyError = !headerKey
+      ? input.t('settings.providers.page.custom.error.required')
+      : seenHeaders.has(headerKey.toLowerCase())
+        ? input.t('settings.providers.page.custom.error.duplicate')
+        : (() => {
+            seenHeaders.add(headerKey.toLowerCase());
+            return undefined;
+          })();
+    const valueError = !headerValue
+      ? input.t('settings.providers.page.custom.error.required')
+      : undefined;
+    return { key: keyError, value: valueError };
+  });
+
+  const headersValid = headerErrors.every((entry) => !entry.key && !entry.value);
+  const headerConfig = Object.fromEntries(
+    input.form.headers
+      .map((header) => ({ key: header.key.trim(), value: header.value.trim() }))
+      .filter((header) => header.key && header.value)
+      .map((header) => [header.key, header.value]),
+  );
+
+  const err: FieldErrors = {
+    providerID: idError ?? existsError,
+    name: nameError,
+    baseURL: urlError,
+  };
+
+  const ok = !idError && !existsError && !nameError && !urlError && modelsValid && headersValid;
+  if (!ok) {
+    return { err, models: modelErrors, headers: headerErrors };
+  }
+
+  return {
+    err,
+    models: modelErrors,
+    headers: headerErrors,
+    result: {
+      providerID,
+      name,
+      apiKey: key,
+      config: {
+        npm: CUSTOM_PROVIDER_NPM,
+        name,
+        ...(env ? { env: [env] } : {}),
+        options: {
+          baseURL,
+          ...(Object.keys(headerConfig).length > 0 ? { headers: headerConfig } : {}),
+        },
+        models: modelConfig,
+      },
+    },
+  };
+}
+
+/**
+ * Builds the OpenCode auth.set request body when a literal API key is present.
+ */
+export function buildAuthSetRequest(plan: CustomProviderPersistPlan): {
+  providerID: string;
+  auth: { type: 'api'; key: string };
+} | null {
+  if (!plan.apiKey) {
+    return null;
+  }
+  return {
+    providerID: plan.providerID,
+    auth: { type: 'api', key: plan.apiKey },
+  };
+}
+
+/**
+ * Builds the OpenChamber provider upsert request body (config persistence).
+ */
+export function buildProviderUpsertRequest(plan: CustomProviderPersistPlan): {
+  providerID: string;
+  config: CustomProviderConfig;
+} {
+  return {
+    providerID: plan.providerID,
+    config: plan.config,
+  };
+}
+
+/**
+ * Merges a custom provider block into an existing OpenCode config object.
+ * Used by persistence tests and mirrors server upsert semantics.
+ */
+export function mergeProviderConfig(
+  existing: Record<string, unknown>,
+  providerID: string,
+  config: CustomProviderConfig,
+  options?: { removeFromDisabled?: boolean },
+): Record<string, unknown> {
+  const providerSection = (
+    typeof existing.provider === 'object' && existing.provider !== null && !Array.isArray(existing.provider)
+      ? { ...(existing.provider as Record<string, unknown>) }
+      : {}
+  );
+  providerSection[providerID] = config;
+
+  const next: Record<string, unknown> = {
+    ...existing,
+    provider: providerSection,
+  };
+
+  if (options?.removeFromDisabled !== false && Array.isArray(existing.disabled_providers)) {
+    next.disabled_providers = existing.disabled_providers.filter(
+      (entry) => entry !== providerID,
+    );
+  }
+
+  return next;
+}
diff --git a/packages/ui/src/lib/i18n/messages/en.settings.ts b/packages/ui/src/lib/i18n/messages/en.settings.ts
index 5eac5495..c8ad2081 100644
--- a/packages/ui/src/lib/i18n/messages/en.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/en.settings.ts
@@ -1334,6 +1334,46 @@ export const settingsDict = {
   'settings.providers.page.connect.searchProvidersPlaceholder': 'Search...',
   'settings.providers.page.connect.noProvidersFound': 'No providers found',
   'settings.providers.page.connect.allProvidersConnected': 'All providers connected.',
+  'settings.providers.page.custom.optionLabel': 'Other / Custom',
+  'settings.providers.page.custom.title': 'Custom provider',
+  'settings.providers.page.custom.description': 'Add an OpenAI-compatible provider with a base URL, credentials, and model list. Saved to OpenCode config so it works in chat like any other provider.',
+  'settings.providers.page.custom.field.providerID.label': 'Provider ID',
+  'settings.providers.page.custom.field.providerID.placeholder': 'my-provider',
+  'settings.providers.page.custom.field.providerID.info': 'Lowercase letters, numbers, hyphens, and underscores. Used as the OpenCode provider id.',
+  'settings.providers.page.custom.field.name.label': 'Display name',
+  'settings.providers.page.custom.field.name.placeholder': 'My Provider',
+  'settings.providers.page.custom.field.name.info': 'Shown in the provider and model pickers.',
+  'settings.providers.page.custom.field.baseURL.label': 'Base URL',
+  'settings.providers.page.custom.field.baseURL.placeholder': 'https://api.example.com/v1',
+  'settings.providers.page.custom.field.baseURL.info': 'OpenAI-compatible API base URL. Must start with http:// or https://.',
+  'settings.providers.page.custom.field.apiKey.label': 'API key',
+  'settings.providers.page.custom.field.apiKey.placeholder': 'sk-... or {env:VAR_NAME}',
+  'settings.providers.page.custom.field.apiKey.info': 'Stored in OpenCode auth, not by OpenChamber. Use {env:VAR_NAME} to read a key from the environment instead.',
+  'settings.providers.page.custom.models.title': 'Models',
+  'settings.providers.page.custom.models.idLabel': 'Model ID',
+  'settings.providers.page.custom.models.idPlaceholder': 'gpt-4o',
+  'settings.providers.page.custom.models.nameLabel': 'Model name',
+  'settings.providers.page.custom.models.namePlaceholder': 'GPT-4o',
+  'settings.providers.page.custom.models.add': 'Add model',
+  'settings.providers.page.custom.models.remove': 'Remove model',
+  'settings.providers.page.custom.headers.title': 'Headers',
+  'settings.providers.page.custom.headers.description': 'Optional request headers sent with every call.',
+  'settings.providers.page.custom.headers.keyLabel': 'Header name',
+  'settings.providers.page.custom.headers.keyPlaceholder': 'X-Custom-Header',
+  'settings.providers.page.custom.headers.valueLabel': 'Header value',
+  'settings.providers.page.custom.headers.valuePlaceholder': 'value',
+  'settings.providers.page.custom.headers.add': 'Add header',
+  'settings.providers.page.custom.headers.remove': 'Remove header',
+  'settings.providers.page.custom.actions.back': 'Back',
+  'settings.providers.page.custom.actions.save': 'Save provider',
+  'settings.providers.page.custom.error.providerID.required': 'Provider ID is required',
+  'settings.providers.page.custom.error.providerID.format': 'Use lowercase letters, numbers, hyphens, or underscores',
+  'settings.providers.page.custom.error.providerID.exists': 'A provider with this ID is already connected',
+  'settings.providers.page.custom.error.name.required': 'Display name is required',
+  'settings.providers.page.custom.error.baseURL.required': 'Base URL is required',
+  'settings.providers.page.custom.error.baseURL.format': 'Base URL must start with http:// or https://',
+  'settings.providers.page.custom.error.required': 'Required',
+  'settings.providers.page.custom.error.duplicate': 'Duplicate',
   'settings.providers.page.auth.title': 'Authentication',
   'settings.providers.page.auth.loadingMethods': 'Loading authentication methods...',
   'settings.providers.page.auth.apiKeyLabel': 'API Key',
@@ -1391,6 +1431,8 @@ export const settingsDict = {
   'settings.providers.page.toast.deviceCodeCopyFailed': 'Failed to copy device code',
   'settings.providers.page.toast.providerDisconnected': 'Provider disconnected',
   'settings.providers.page.toast.providerDisconnectFailed': 'Failed to disconnect provider',
+  'settings.providers.page.toast.customProviderSaved': '{provider} connected',
+  'settings.providers.page.toast.customProviderSaveFailed': 'Failed to save custom provider',
   'settings.mcp.page.empty.selectServer': 'Select an MCP server from the sidebar',
   'settings.mcp.page.empty.addNewOne': 'or add a new one',
   'settings.mcp.page.header.newServer': 'New MCP Server',
diff --git a/packages/ui/src/lib/i18n/messages/es.settings.ts b/packages/ui/src/lib/i18n/messages/es.settings.ts
index dfaf6c11..4d12d1bb 100644
--- a/packages/ui/src/lib/i18n/messages/es.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/es.settings.ts
@@ -1301,6 +1301,46 @@ export const settingsDict = {
   "settings.providers.page.connect.searchProvidersPlaceholder": "Buscar...",
   "settings.providers.page.connect.noProvidersFound": "No se encontraron proveedores",
   "settings.providers.page.connect.allProvidersConnected": "Todos los proveedores están conectados.",
+  "settings.providers.page.custom.optionLabel": "Otro / Personalizado",
+  "settings.providers.page.custom.title": "Proveedor personalizado",
+  "settings.providers.page.custom.description": "Añade un proveedor compatible con OpenAI con URL base, credenciales y lista de modelos. Se guarda en la configuración de OpenCode para usarlo en el chat como cualquier otro proveedor.",
+  "settings.providers.page.custom.field.providerID.label": "ID del proveedor",
+  "settings.providers.page.custom.field.providerID.placeholder": "mi-proveedor",
+  "settings.providers.page.custom.field.providerID.info": "Minúsculas, números, guiones y guiones bajos. Se usa como ID de proveedor de OpenCode.",
+  "settings.providers.page.custom.field.name.label": "Nombre visible",
+  "settings.providers.page.custom.field.name.placeholder": "Mi proveedor",
+  "settings.providers.page.custom.field.name.info": "Se muestra en los selectores de proveedor y modelo.",
+  "settings.providers.page.custom.field.baseURL.label": "URL base",
+  "settings.providers.page.custom.field.baseURL.placeholder": "https://api.example.com/v1",
+  "settings.providers.page.custom.field.baseURL.info": "URL base de la API compatible con OpenAI. Debe empezar por http:// o https://.",
+  "settings.providers.page.custom.field.apiKey.label": "Clave API",
+  "settings.providers.page.custom.field.apiKey.placeholder": "sk-... o {env:VAR_NAME}",
+  "settings.providers.page.custom.field.apiKey.info": "Se guarda en la autenticación de OpenCode, no en OpenChamber. Usa {env:VAR_NAME} para leer una clave del entorno.",
+  "settings.providers.page.custom.models.title": "Modelos",
+  "settings.providers.page.custom.models.idLabel": "ID del modelo",
+  "settings.providers.page.custom.models.idPlaceholder": "gpt-4o",
+  "settings.providers.page.custom.models.nameLabel": "Nombre del modelo",
+  "settings.providers.page.custom.models.namePlaceholder": "GPT-4o",
+  "settings.providers.page.custom.models.add": "Añadir modelo",
+  "settings.providers.page.custom.models.remove": "Quitar modelo",
+  "settings.providers.page.custom.headers.title": "Encabezados",
+  "settings.providers.page.custom.headers.description": "Encabezados de solicitud opcionales enviados en cada llamada.",
+  "settings.providers.page.custom.headers.keyLabel": "Nombre del encabezado",
+  "settings.providers.page.custom.headers.keyPlaceholder": "X-Custom-Header",
+  "settings.providers.page.custom.headers.valueLabel": "Valor del encabezado",
+  "settings.providers.page.custom.headers.valuePlaceholder": "valor",
+  "settings.providers.page.custom.headers.add": "Añadir encabezado",
+  "settings.providers.page.custom.headers.remove": "Quitar encabezado",
+  "settings.providers.page.custom.actions.back": "Atrás",
+  "settings.providers.page.custom.actions.save": "Guardar proveedor",
+  "settings.providers.page.custom.error.providerID.required": "El ID del proveedor es obligatorio",
+  "settings.providers.page.custom.error.providerID.format": "Usa minúsculas, números, guiones o guiones bajos",
+  "settings.providers.page.custom.error.providerID.exists": "Ya hay un proveedor conectado con este ID",
+  "settings.providers.page.custom.error.name.required": "El nombre visible es obligatorio",
+  "settings.providers.page.custom.error.baseURL.required": "La URL base es obligatoria",
+  "settings.providers.page.custom.error.baseURL.format": "La URL base debe empezar por http:// o https://",
+  "settings.providers.page.custom.error.required": "Obligatorio",
+  "settings.providers.page.custom.error.duplicate": "Duplicado",
   "settings.providers.page.auth.title": "Autenticación",
   "settings.providers.page.auth.loadingMethods": "Cargando métodos de autenticación...",
   "settings.providers.page.auth.apiKeyLabel": "Clave API",
@@ -1358,6 +1398,8 @@ export const settingsDict = {
   "settings.providers.page.toast.deviceCodeCopyFailed": "No se pudo copiar el código de dispositivo",
   "settings.providers.page.toast.providerDisconnected": "Proveedor desconectado",
   "settings.providers.page.toast.providerDisconnectFailed": "No se pudo desconectar el proveedor",
+  "settings.providers.page.toast.customProviderSaved": "{provider} conectado",
+  "settings.providers.page.toast.customProviderSaveFailed": "No se pudo guardar el proveedor personalizado",
   "settings.mcp.page.empty.selectServer": "Selecciona un servidor MCP desde el panel lateral",
   "settings.mcp.page.empty.addNewOne": "o añade uno nuevo",
   "settings.mcp.page.header.newServer": "Nuevo servidor MCP",
diff --git a/packages/ui/src/lib/i18n/messages/fr.settings.ts b/packages/ui/src/lib/i18n/messages/fr.settings.ts
index 46dbd110..cc054a10 100644
--- a/packages/ui/src/lib/i18n/messages/fr.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/fr.settings.ts
@@ -1222,6 +1222,46 @@ export const settingsDict = {
   'settings.providers.page.connect.searchProvidersPlaceholder': 'Recherche...',
   'settings.providers.page.connect.noProvidersFound': 'Aucun fournisseur trouvé',
   'settings.providers.page.connect.allProvidersConnected': 'Tous les fournisseurs connectés.',
+  'settings.providers.page.custom.optionLabel': 'Autre / Personnalisé',
+  'settings.providers.page.custom.title': 'Fournisseur personnalisé',
+  'settings.providers.page.custom.description': 'Ajoutez un fournisseur compatible OpenAI avec une URL de base, des identifiants et une liste de modèles. Enregistré dans la configuration OpenCode pour l’utiliser dans le chat comme les autres fournisseurs.',
+  'settings.providers.page.custom.field.providerID.label': 'ID du fournisseur',
+  'settings.providers.page.custom.field.providerID.placeholder': 'mon-fournisseur',
+  'settings.providers.page.custom.field.providerID.info': 'Minuscules, chiffres, tirets et underscores. Utilisé comme ID de fournisseur OpenCode.',
+  'settings.providers.page.custom.field.name.label': 'Nom affiché',
+  'settings.providers.page.custom.field.name.placeholder': 'Mon fournisseur',
+  'settings.providers.page.custom.field.name.info': 'Affiché dans les sélecteurs de fournisseur et de modèle.',
+  'settings.providers.page.custom.field.baseURL.label': 'URL de base',
+  'settings.providers.page.custom.field.baseURL.placeholder': 'https://api.example.com/v1',
+  'settings.providers.page.custom.field.baseURL.info': 'URL de base de l’API compatible OpenAI. Doit commencer par http:// ou https://.',
+  'settings.providers.page.custom.field.apiKey.label': 'Clé API',
+  'settings.providers.page.custom.field.apiKey.placeholder': 'sk-... ou {env:VAR_NAME}',
+  'settings.providers.page.custom.field.apiKey.info': 'Stockée dans l’auth OpenCode, pas par OpenChamber. Utilisez {env:VAR_NAME} pour lire une clé depuis l’environnement.',
+  'settings.providers.page.custom.models.title': 'Modèles',
+  'settings.providers.page.custom.models.idLabel': 'ID du modèle',
+  'settings.providers.page.custom.models.idPlaceholder': 'gpt-4o',
+  'settings.providers.page.custom.models.nameLabel': 'Nom du modèle',
+  'settings.providers.page.custom.models.namePlaceholder': 'GPT-4o',
+  'settings.providers.page.custom.models.add': 'Ajouter un modèle',
+  'settings.providers.page.custom.models.remove': 'Supprimer le modèle',
+  'settings.providers.page.custom.headers.title': 'En-têtes',
+  'settings.providers.page.custom.headers.description': 'En-têtes de requête optionnels envoyés à chaque appel.',
+  'settings.providers.page.custom.headers.keyLabel': 'Nom de l’en-tête',
+  'settings.providers.page.custom.headers.keyPlaceholder': 'X-Custom-Header',
+  'settings.providers.page.custom.headers.valueLabel': 'Valeur de l’en-tête',
+  'settings.providers.page.custom.headers.valuePlaceholder': 'valeur',
+  'settings.providers.page.custom.headers.add': 'Ajouter un en-tête',
+  'settings.providers.page.custom.headers.remove': 'Supprimer l’en-tête',
+  'settings.providers.page.custom.actions.back': 'Retour',
+  'settings.providers.page.custom.actions.save': 'Enregistrer le fournisseur',
+  'settings.providers.page.custom.error.providerID.required': 'L’ID du fournisseur est obligatoire',
+  'settings.providers.page.custom.error.providerID.format': 'Utilisez des minuscules, chiffres, tirets ou underscores',
+  'settings.providers.page.custom.error.providerID.exists': 'Un fournisseur avec cet ID est déjà connecté',
+  'settings.providers.page.custom.error.name.required': 'Le nom affiché est obligatoire',
+  'settings.providers.page.custom.error.baseURL.required': 'L’URL de base est obligatoire',
+  'settings.providers.page.custom.error.baseURL.format': 'L’URL de base doit commencer par http:// ou https://',
+  'settings.providers.page.custom.error.required': 'Obligatoire',
+  'settings.providers.page.custom.error.duplicate': 'Doublon',
   'settings.providers.page.auth.title': 'Authentification',
   'settings.providers.page.auth.loadingMethods': 'Chargement des méthodes d\'authentification...',
   'settings.providers.page.auth.apiKeyLabel': 'Clé API',
@@ -1279,6 +1319,8 @@ export const settingsDict = {
   'settings.providers.page.toast.deviceCodeCopyFailed': 'Échec de la copie du code de l\'appareil',
   'settings.providers.page.toast.providerDisconnected': 'Fournisseur déconnecté',
   'settings.providers.page.toast.providerDisconnectFailed': 'Échec de la déconnexion du fournisseur',
+  'settings.providers.page.toast.customProviderSaved': '{provider} connecté',
+  'settings.providers.page.toast.customProviderSaveFailed': 'Échec de l’enregistrement du fournisseur personnalisé',
   'settings.mcp.page.empty.selectServer': 'Sélectionnez un serveur MCP dans la barre latérale',
   'settings.mcp.page.empty.addNewOne': 'ou ajoutez-en un nouveau',
   'settings.mcp.page.header.newServer': 'Nouveau serveur MCP',
diff --git a/packages/ui/src/lib/i18n/messages/ja.settings.ts b/packages/ui/src/lib/i18n/messages/ja.settings.ts
index adfa17bb..bfe95958 100644
--- a/packages/ui/src/lib/i18n/messages/ja.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/ja.settings.ts
@@ -1334,6 +1334,46 @@ export const settingsDict = {
   'settings.providers.page.connect.searchProvidersPlaceholder': '検索...',
   'settings.providers.page.connect.noProvidersFound': 'Provider が見つかりません',
   'settings.providers.page.connect.allProvidersConnected': 'すべての Provider が接続されています。',
+  'settings.providers.page.custom.optionLabel': 'その他 / カスタム',
+  'settings.providers.page.custom.title': 'カスタムプロバイダー',
+  'settings.providers.page.custom.description': 'ベース URL・認証情報・モデル一覧を指定して、OpenAI 互換プロバイダーを追加します。OpenCode 設定に保存され、他のプロバイダーと同様にチャットで使えます。',
+  'settings.providers.page.custom.field.providerID.label': 'プロバイダー ID',
+  'settings.providers.page.custom.field.providerID.placeholder': 'my-provider',
+  'settings.providers.page.custom.field.providerID.info': '小文字・数字・ハイフン・アンダースコア。OpenCode のプロバイダー ID として使われます。',
+  'settings.providers.page.custom.field.name.label': '表示名',
+  'settings.providers.page.custom.field.name.placeholder': 'My Provider',
+  'settings.providers.page.custom.field.name.info': 'プロバイダーおよびモデル選択に表示されます。',
+  'settings.providers.page.custom.field.baseURL.label': 'ベース URL',
+  'settings.providers.page.custom.field.baseURL.placeholder': 'https://api.example.com/v1',
+  'settings.providers.page.custom.field.baseURL.info': 'OpenAI 互換 API のベース URL。http:// または https:// で始めてください。',
+  'settings.providers.page.custom.field.apiKey.label': 'API キー',
+  'settings.providers.page.custom.field.apiKey.placeholder': 'sk-... または {env:VAR_NAME}',
+  'settings.providers.page.custom.field.apiKey.info': 'OpenChamber ではなく OpenCode の認証に保存されます。環境変数から読む場合は {env:VAR_NAME} を使います。',
+  'settings.providers.page.custom.models.title': 'モデル',
+  'settings.providers.page.custom.models.idLabel': 'モデル ID',
+  'settings.providers.page.custom.models.idPlaceholder': 'gpt-4o',
+  'settings.providers.page.custom.models.nameLabel': 'モデル名',
+  'settings.providers.page.custom.models.namePlaceholder': 'GPT-4o',
+  'settings.providers.page.custom.models.add': 'モデルを追加',
+  'settings.providers.page.custom.models.remove': 'モデルを削除',
+  'settings.providers.page.custom.headers.title': 'ヘッダー',
+  'settings.providers.page.custom.headers.description': '各リクエストに付ける任意のヘッダーです。',
+  'settings.providers.page.custom.headers.keyLabel': 'ヘッダー名',
+  'settings.providers.page.custom.headers.keyPlaceholder': 'X-Custom-Header',
+  'settings.providers.page.custom.headers.valueLabel': 'ヘッダー値',
+  'settings.providers.page.custom.headers.valuePlaceholder': 'value',
+  'settings.providers.page.custom.headers.add': 'ヘッダーを追加',
+  'settings.providers.page.custom.headers.remove': 'ヘッダーを削除',
+  'settings.providers.page.custom.actions.back': '戻る',
+  'settings.providers.page.custom.actions.save': 'プロバイダーを保存',
+  'settings.providers.page.custom.error.providerID.required': 'プロバイダー ID は必須です',
+  'settings.providers.page.custom.error.providerID.format': '小文字・数字・ハイフン・アンダースコアを使ってください',
+  'settings.providers.page.custom.error.providerID.exists': 'この ID のプロバイダーは既に接続されています',
+  'settings.providers.page.custom.error.name.required': '表示名は必須です',
+  'settings.providers.page.custom.error.baseURL.required': 'ベース URL は必須です',
+  'settings.providers.page.custom.error.baseURL.format': 'ベース URL は http:// または https:// で始めてください',
+  'settings.providers.page.custom.error.required': '必須',
+  'settings.providers.page.custom.error.duplicate': '重複',
   'settings.providers.page.auth.title': '認証',
   'settings.providers.page.auth.loadingMethods': '認証方法を読み込み中...',
   'settings.providers.page.auth.apiKeyLabel': 'API キー',
@@ -1391,6 +1431,8 @@ export const settingsDict = {
   'settings.providers.page.toast.deviceCodeCopyFailed': 'デバイスコードのコピーに失敗しました',
   'settings.providers.page.toast.providerDisconnected': 'Provider を切断しました',
   'settings.providers.page.toast.providerDisconnectFailed': 'Provider の切断に失敗しました',
+  'settings.providers.page.toast.customProviderSaved': '{provider} を接続しました',
+  'settings.providers.page.toast.customProviderSaveFailed': 'カスタムプロバイダーの保存に失敗しました',
   'settings.mcp.page.empty.selectServer': 'サイドバーから MCP サーバーを選択してください',
   'settings.mcp.page.empty.addNewOne': 'または新しいものを追加',
   'settings.mcp.page.header.newServer': '新しい MCP サーバー',
diff --git a/packages/ui/src/lib/i18n/messages/ko.settings.ts b/packages/ui/src/lib/i18n/messages/ko.settings.ts
index 810af15d..069abaa3 100644
--- a/packages/ui/src/lib/i18n/messages/ko.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/ko.settings.ts
@@ -1301,6 +1301,46 @@ export const settingsDict = {
   'settings.providers.page.connect.searchProvidersPlaceholder': '검색...',
   'settings.providers.page.connect.noProvidersFound': '프로바이더를 찾을 수 없습니다',
   'settings.providers.page.connect.allProvidersConnected': '모든 프로바이더가 연결되었습니다.',
+  'settings.providers.page.custom.optionLabel': '기타 / 사용자 정의',
+  'settings.providers.page.custom.title': '사용자 정의 제공자',
+  'settings.providers.page.custom.description': '기본 URL, 자격 증명, 모델 목록으로 OpenAI 호환 제공자를 추가합니다. OpenCode 설정에 저장되어 다른 제공자와 같이 채팅에서 사용할 수 있습니다.',
+  'settings.providers.page.custom.field.providerID.label': '제공자 ID',
+  'settings.providers.page.custom.field.providerID.placeholder': 'my-provider',
+  'settings.providers.page.custom.field.providerID.info': '소문자, 숫자, 하이픈, 밑줄. OpenCode 제공자 ID로 사용됩니다.',
+  'settings.providers.page.custom.field.name.label': '표시 이름',
+  'settings.providers.page.custom.field.name.placeholder': '내 제공자',
+  'settings.providers.page.custom.field.name.info': '제공자 및 모델 선택기에 표시됩니다.',
+  'settings.providers.page.custom.field.baseURL.label': '기본 URL',
+  'settings.providers.page.custom.field.baseURL.placeholder': 'https://api.example.com/v1',
+  'settings.providers.page.custom.field.baseURL.info': 'OpenAI 호환 API 기본 URL. http:// 또는 https://로 시작해야 합니다.',
+  'settings.providers.page.custom.field.apiKey.label': 'API 키',
+  'settings.providers.page.custom.field.apiKey.placeholder': 'sk-... 또는 {env:VAR_NAME}',
+  'settings.providers.page.custom.field.apiKey.info': 'OpenChamber가 아니라 OpenCode 인증에 저장됩니다. 환경 변수에서 읽으려면 {env:VAR_NAME}을 사용하세요.',
+  'settings.providers.page.custom.models.title': '모델',
+  'settings.providers.page.custom.models.idLabel': '모델 ID',
+  'settings.providers.page.custom.models.idPlaceholder': 'gpt-4o',
+  'settings.providers.page.custom.models.nameLabel': '모델 이름',
+  'settings.providers.page.custom.models.namePlaceholder': 'GPT-4o',
+  'settings.providers.page.custom.models.add': '모델 추가',
+  'settings.providers.page.custom.models.remove': '모델 제거',
+  'settings.providers.page.custom.headers.title': '헤더',
+  'settings.providers.page.custom.headers.description': '매 호출에 전송되는 선택적 요청 헤더입니다.',
+  'settings.providers.page.custom.headers.keyLabel': '헤더 이름',
+  'settings.providers.page.custom.headers.keyPlaceholder': 'X-Custom-Header',
+  'settings.providers.page.custom.headers.valueLabel': '헤더 값',
+  'settings.providers.page.custom.headers.valuePlaceholder': 'value',
+  'settings.providers.page.custom.headers.add': '헤더 추가',
+  'settings.providers.page.custom.headers.remove': '헤더 제거',
+  'settings.providers.page.custom.actions.back': '뒤로',
+  'settings.providers.page.custom.actions.save': '제공자 저장',
+  'settings.providers.page.custom.error.providerID.required': '제공자 ID는 필수입니다',
+  'settings.providers.page.custom.error.providerID.format': '소문자, 숫자, 하이픈, 밑줄을 사용하세요',
+  'settings.providers.page.custom.error.providerID.exists': '이 ID의 제공자가 이미 연결되어 있습니다',
+  'settings.providers.page.custom.error.name.required': '표시 이름은 필수입니다',
+  'settings.providers.page.custom.error.baseURL.required': '기본 URL은 필수입니다',
+  'settings.providers.page.custom.error.baseURL.format': '기본 URL은 http:// 또는 https://로 시작해야 합니다',
+  'settings.providers.page.custom.error.required': '필수',
+  'settings.providers.page.custom.error.duplicate': '중복',
   'settings.providers.page.auth.title': '인증',
   'settings.providers.page.auth.loadingMethods': '인증 방식 로딩 중...',
   'settings.providers.page.auth.apiKeyLabel': 'API Key',
@@ -1358,6 +1398,8 @@ export const settingsDict = {
   'settings.providers.page.toast.deviceCodeCopyFailed': '기기 코드를 복사하지 못했습니다',
   'settings.providers.page.toast.providerDisconnected': '프로바이더 연결이 해제되었습니다',
   'settings.providers.page.toast.providerDisconnectFailed': '프로바이더 연결을 해제하지 못했습니다',
+  'settings.providers.page.toast.customProviderSaved': '{provider} 연결됨',
+  'settings.providers.page.toast.customProviderSaveFailed': '사용자 정의 제공자를 저장하지 못했습니다',
   'settings.mcp.page.empty.selectServer': '사이드바에서 MCP 서버를 선택하세요',
   'settings.mcp.page.empty.addNewOne': '또는 새로 추가하세요',
   'settings.mcp.page.header.newServer': '새 MCP 서버',
diff --git a/packages/ui/src/lib/i18n/messages/pl.settings.ts b/packages/ui/src/lib/i18n/messages/pl.settings.ts
index f102e2ec..26aeea46 100644
--- a/packages/ui/src/lib/i18n/messages/pl.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/pl.settings.ts
@@ -1377,6 +1377,46 @@ export const settingsDict = {
   'settings.providers.page.auth.title': 'Uwierzytelnianie',
   'settings.providers.page.auth.useReconnectHint': '· Użyj Połącz ponownie, aby zaktualizować dane logowania',
   'settings.providers.page.connect.allProvidersConnected': 'Wszyscy dostawcy są połączeni.',
+  'settings.providers.page.custom.optionLabel': 'Inny / Niestandardowy',
+  'settings.providers.page.custom.title': 'Niestandardowy dostawca',
+  'settings.providers.page.custom.description': 'Dodaj dostawcę zgodnego z OpenAI, podając adres bazowy, poświadczenia i listę modeli. Zapisuje się w konfiguracji OpenCode i działa w czacie jak każdy inny dostawca.',
+  'settings.providers.page.custom.field.providerID.label': 'ID dostawcy',
+  'settings.providers.page.custom.field.providerID.placeholder': 'moj-dostawca',
+  'settings.providers.page.custom.field.providerID.info': 'Małe litery, cyfry, myślniki i podkreślenia. Używane jako ID dostawcy OpenCode.',
+  'settings.providers.page.custom.field.name.label': 'Nazwa wyświetlana',
+  'settings.providers.page.custom.field.name.placeholder': 'Mój dostawca',
+  'settings.providers.page.custom.field.name.info': 'Widoczna w selektorach dostawcy i modelu.',
+  'settings.providers.page.custom.field.baseURL.label': 'Adres bazowy',
+  'settings.providers.page.custom.field.baseURL.placeholder': 'https://api.example.com/v1',
+  'settings.providers.page.custom.field.baseURL.info': 'Bazowy URL API zgodnego z OpenAI. Musi zaczynać się od http:// lub https://.',
+  'settings.providers.page.custom.field.apiKey.label': 'Klucz API',
+  'settings.providers.page.custom.field.apiKey.placeholder': 'sk-... lub {env:VAR_NAME}',
+  'settings.providers.page.custom.field.apiKey.info': 'Przechowywany w auth OpenCode, nie przez OpenChamber. Użyj {env:VAR_NAME}, aby odczytać klucz ze zmiennej środowiskowej.',
+  'settings.providers.page.custom.models.title': 'Modele',
+  'settings.providers.page.custom.models.idLabel': 'ID modelu',
+  'settings.providers.page.custom.models.idPlaceholder': 'gpt-4o',
+  'settings.providers.page.custom.models.nameLabel': 'Nazwa modelu',
+  'settings.providers.page.custom.models.namePlaceholder': 'GPT-4o',
+  'settings.providers.page.custom.models.add': 'Dodaj model',
+  'settings.providers.page.custom.models.remove': 'Usuń model',
+  'settings.providers.page.custom.headers.title': 'Nagłówki',
+  'settings.providers.page.custom.headers.description': 'Opcjonalne nagłówki żądania wysyłane przy każdym wywołaniu.',
+  'settings.providers.page.custom.headers.keyLabel': 'Nazwa nagłówka',
+  'settings.providers.page.custom.headers.keyPlaceholder': 'X-Custom-Header',
+  'settings.providers.page.custom.headers.valueLabel': 'Wartość nagłówka',
+  'settings.providers.page.custom.headers.valuePlaceholder': 'wartość',
+  'settings.providers.page.custom.headers.add': 'Dodaj nagłówek',
+  'settings.providers.page.custom.headers.remove': 'Usuń nagłówek',
+  'settings.providers.page.custom.actions.back': 'Wstecz',
+  'settings.providers.page.custom.actions.save': 'Zapisz dostawcę',
+  'settings.providers.page.custom.error.providerID.required': 'ID dostawcy jest wymagane',
+  'settings.providers.page.custom.error.providerID.format': 'Użyj małych liter, cyfr, myślników lub podkreśleń',
+  'settings.providers.page.custom.error.providerID.exists': 'Dostawca o tym ID jest już połączony',
+  'settings.providers.page.custom.error.name.required': 'Nazwa wyświetlana jest wymagana',
+  'settings.providers.page.custom.error.baseURL.required': 'Adres bazowy jest wymagany',
+  'settings.providers.page.custom.error.baseURL.format': 'Adres bazowy musi zaczynać się od http:// lub https://',
+  'settings.providers.page.custom.error.required': 'Wymagane',
+  'settings.providers.page.custom.error.duplicate': 'Duplikat',
   'settings.providers.page.connect.noProvidersFound': 'Nie znaleziono dostawców',
   'settings.providers.page.connect.providerField': 'Dostawca',
   'settings.providers.page.connect.searchProvidersPlaceholder': 'Szukaj...',
@@ -1422,6 +1462,8 @@ export const settingsDict = {
   'settings.providers.page.toast.oauthLinkCopyFailed': 'Nie udało się skopiować linku OAuth',
   'settings.providers.page.toast.oauthStartFailed': 'Nie udało się rozpocząć procesu OAuth',
   'settings.providers.page.toast.providerDisconnectFailed': 'Nie udało się odłączyć dostawcy',
+  'settings.providers.page.toast.customProviderSaved': 'Połączono {provider}',
+  'settings.providers.page.toast.customProviderSaveFailed': 'Nie udało się zapisać niestandardowego dostawcy',
   'settings.providers.page.toast.providerDisconnected': 'Dostawca został odłączony',
   'settings.providers.page.toast.providerSourcesLoadFailed': 'Nie udało się załadować źródeł dostawcy',
   'settings.providers.sidebar.actions.connectProviderAria': 'Połącz dostawcę',
diff --git a/packages/ui/src/lib/i18n/messages/pt-BR.settings.ts b/packages/ui/src/lib/i18n/messages/pt-BR.settings.ts
index 2870ca26..845e6d69 100644
--- a/packages/ui/src/lib/i18n/messages/pt-BR.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/pt-BR.settings.ts
@@ -1301,6 +1301,46 @@ export const settingsDict = {
   "settings.providers.page.connect.searchProvidersPlaceholder": "Buscar...",
   "settings.providers.page.connect.noProvidersFound": "Nenhum provedores",
   "settings.providers.page.connect.allProvidersConnected": "Todos os provedores estão conectados.",
+  "settings.providers.page.custom.optionLabel": "Outro / Personalizado",
+  "settings.providers.page.custom.title": "Provedor personalizado",
+  "settings.providers.page.custom.description": "Adicione um provedor compatível com OpenAI com URL base, credenciais e lista de modelos. Salvo na configuração do OpenCode para uso no chat como qualquer outro provedor.",
+  "settings.providers.page.custom.field.providerID.label": "ID do provedor",
+  "settings.providers.page.custom.field.providerID.placeholder": "meu-provedor",
+  "settings.providers.page.custom.field.providerID.info": "Letras minúsculas, números, hífens e sublinhados. Usado como ID de provedor do OpenCode.",
+  "settings.providers.page.custom.field.name.label": "Nome de exibição",
+  "settings.providers.page.custom.field.name.placeholder": "Meu provedor",
+  "settings.providers.page.custom.field.name.info": "Mostrado nos seletores de provedor e modelo.",
+  "settings.providers.page.custom.field.baseURL.label": "URL base",
+  "settings.providers.page.custom.field.baseURL.placeholder": "https://api.example.com/v1",
+  "settings.providers.page.custom.field.baseURL.info": "URL base da API compatível com OpenAI. Deve começar com http:// ou https://.",
+  "settings.providers.page.custom.field.apiKey.label": "Chave de API",
+  "settings.providers.page.custom.field.apiKey.placeholder": "sk-... ou {env:VAR_NAME}",
+  "settings.providers.page.custom.field.apiKey.info": "Armazenada na autenticação do OpenCode, não pelo OpenChamber. Use {env:VAR_NAME} para ler uma chave do ambiente.",
+  "settings.providers.page.custom.models.title": "Modelos",
+  "settings.providers.page.custom.models.idLabel": "ID do modelo",
+  "settings.providers.page.custom.models.idPlaceholder": "gpt-4o",
+  "settings.providers.page.custom.models.nameLabel": "Nome do modelo",
+  "settings.providers.page.custom.models.namePlaceholder": "GPT-4o",
+  "settings.providers.page.custom.models.add": "Adicionar modelo",
+  "settings.providers.page.custom.models.remove": "Remover modelo",
+  "settings.providers.page.custom.headers.title": "Cabeçalhos",
+  "settings.providers.page.custom.headers.description": "Cabeçalhos de solicitação opcionais enviados em cada chamada.",
+  "settings.providers.page.custom.headers.keyLabel": "Nome do cabeçalho",
+  "settings.providers.page.custom.headers.keyPlaceholder": "X-Custom-Header",
+  "settings.providers.page.custom.headers.valueLabel": "Valor do cabeçalho",
+  "settings.providers.page.custom.headers.valuePlaceholder": "valor",
+  "settings.providers.page.custom.headers.add": "Adicionar cabeçalho",
+  "settings.providers.page.custom.headers.remove": "Remover cabeçalho",
+  "settings.providers.page.custom.actions.back": "Voltar",
+  "settings.providers.page.custom.actions.save": "Salvar provedor",
+  "settings.providers.page.custom.error.providerID.required": "O ID do provedor é obrigatório",
+  "settings.providers.page.custom.error.providerID.format": "Use letras minúsculas, números, hífens ou sublinhados",
+  "settings.providers.page.custom.error.providerID.exists": "Já existe um provedor conectado com este ID",
+  "settings.providers.page.custom.error.name.required": "O nome de exibição é obrigatório",
+  "settings.providers.page.custom.error.baseURL.required": "A URL base é obrigatória",
+  "settings.providers.page.custom.error.baseURL.format": "A URL base deve começar com http:// ou https://",
+  "settings.providers.page.custom.error.required": "Obrigatório",
+  "settings.providers.page.custom.error.duplicate": "Duplicado",
   "settings.providers.page.auth.title": "Autenticação",
   "settings.providers.page.auth.loadingMethods": "Carregando métodos de autenticação...",
   "settings.providers.page.auth.apiKeyLabel": "Chave API",
@@ -1358,6 +1398,8 @@ export const settingsDict = {
   "settings.providers.page.toast.deviceCodeCopyFailed": "Não foi possível copiar o código de dispositivo",
   "settings.providers.page.toast.providerDisconnected": "Provedor desconectado",
   "settings.providers.page.toast.providerDisconnectFailed": "Não foi possível desconectar o provedor",
+  "settings.providers.page.toast.customProviderSaved": "{provider} conectado",
+  "settings.providers.page.toast.customProviderSaveFailed": "Falha ao salvar o provedor personalizado",
   "settings.mcp.page.empty.selectServer": "Selecione um servidor MCP de o painel lateral",
   "settings.mcp.page.empty.addNewOne": "o añade um novo",
   "settings.mcp.page.header.newServer": "Novo servidor MCP",
diff --git a/packages/ui/src/lib/i18n/messages/uk.settings.ts b/packages/ui/src/lib/i18n/messages/uk.settings.ts
index 09bab6b9..740b38ba 100644
--- a/packages/ui/src/lib/i18n/messages/uk.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/uk.settings.ts
@@ -1301,6 +1301,46 @@ export const settingsDict = {
   "settings.providers.page.connect.searchProvidersPlaceholder": "Пошук...",
   "settings.providers.page.connect.noProvidersFound": "Немає провайдерів",
   "settings.providers.page.connect.allProvidersConnected": "Усі провайдери підключені.",
+  "settings.providers.page.custom.optionLabel": "Інший / Власний",
+  "settings.providers.page.custom.title": "Власний провайдер",
+  "settings.providers.page.custom.description": "Додайте OpenAI-сумісного провайдера з базовою URL-адресою, обліковими даними та списком моделей. Зберігається в конфігурації OpenCode й працює в чаті як будь-який інший провайдер.",
+  "settings.providers.page.custom.field.providerID.label": "ID провайдера",
+  "settings.providers.page.custom.field.providerID.placeholder": "mij-provider",
+  "settings.providers.page.custom.field.providerID.info": "Малі літери, цифри, дефіси та підкреслення. Використовується як ID провайдера OpenCode.",
+  "settings.providers.page.custom.field.name.label": "Відображувана назва",
+  "settings.providers.page.custom.field.name.placeholder": "Мій провайдер",
+  "settings.providers.page.custom.field.name.info": "Показується у виборі провайдера та моделі.",
+  "settings.providers.page.custom.field.baseURL.label": "Базова URL-адреса",
+  "settings.providers.page.custom.field.baseURL.placeholder": "https://api.example.com/v1",
+  "settings.providers.page.custom.field.baseURL.info": "Базова URL-адреса OpenAI-сумісного API. Має починатися з http:// або https://.",
+  "settings.providers.page.custom.field.apiKey.label": "API-ключ",
+  "settings.providers.page.custom.field.apiKey.placeholder": "sk-... або {env:VAR_NAME}",
+  "settings.providers.page.custom.field.apiKey.info": "Зберігається в автентифікації OpenCode, не OpenChamber. Використовуйте {env:VAR_NAME}, щоб читати ключ зі змінної середовища.",
+  "settings.providers.page.custom.models.title": "Моделі",
+  "settings.providers.page.custom.models.idLabel": "ID моделі",
+  "settings.providers.page.custom.models.idPlaceholder": "gpt-4o",
+  "settings.providers.page.custom.models.nameLabel": "Назва моделі",
+  "settings.providers.page.custom.models.namePlaceholder": "GPT-4o",
+  "settings.providers.page.custom.models.add": "Додати модель",
+  "settings.providers.page.custom.models.remove": "Видалити модель",
+  "settings.providers.page.custom.headers.title": "Заголовки",
+  "settings.providers.page.custom.headers.description": "Необов’язкові заголовки запиту, що надсилаються з кожним викликом.",
+  "settings.providers.page.custom.headers.keyLabel": "Назва заголовка",
+  "settings.providers.page.custom.headers.keyPlaceholder": "X-Custom-Header",
+  "settings.providers.page.custom.headers.valueLabel": "Значення заголовка",
+  "settings.providers.page.custom.headers.valuePlaceholder": "значення",
+  "settings.providers.page.custom.headers.add": "Додати заголовок",
+  "settings.providers.page.custom.headers.remove": "Видалити заголовок",
+  "settings.providers.page.custom.actions.back": "Назад",
+  "settings.providers.page.custom.actions.save": "Зберегти провайдера",
+  "settings.providers.page.custom.error.providerID.required": "ID провайдера обов’язковий",
+  "settings.providers.page.custom.error.providerID.format": "Використовуйте малі літери, цифри, дефіси або підкреслення",
+  "settings.providers.page.custom.error.providerID.exists": "Провайдер із цим ID уже підключено",
+  "settings.providers.page.custom.error.name.required": "Відображувана назва обов’язкова",
+  "settings.providers.page.custom.error.baseURL.required": "Базова URL-адреса обов’язкова",
+  "settings.providers.page.custom.error.baseURL.format": "Базова URL-адреса має починатися з http:// або https://",
+  "settings.providers.page.custom.error.required": "Обов’язково",
+  "settings.providers.page.custom.error.duplicate": "Дублікат",
   "settings.providers.page.auth.title": "Аутентифікація",
   "settings.providers.page.auth.loadingMethods": "Завантаження методів автентифікації...",
   "settings.providers.page.auth.apiKeyLabel": "API ключ",
@@ -1358,6 +1398,8 @@ export const settingsDict = {
   "settings.providers.page.toast.deviceCodeCopyFailed": "Не вдалося скопіювати код пристрою",
   "settings.providers.page.toast.providerDisconnected": "Провайдера відключено",
   "settings.providers.page.toast.providerDisconnectFailed": "Не вдалося відключити провайдера",
+  "settings.providers.page.toast.customProviderSaved": "{provider} підключено",
+  "settings.providers.page.toast.customProviderSaveFailed": "Не вдалося зберегти власного провайдера",
   "settings.mcp.page.empty.selectServer": "Виберіть MCP сервер на бічній панелі",
   "settings.mcp.page.empty.addNewOne": "або додати новий",
   "settings.mcp.page.header.newServer": "Новий сервер MCP",
diff --git a/packages/ui/src/lib/i18n/messages/zh-CN.settings.ts b/packages/ui/src/lib/i18n/messages/zh-CN.settings.ts
index 43f8f964..88b0b2b0 100644
--- a/packages/ui/src/lib/i18n/messages/zh-CN.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/zh-CN.settings.ts
@@ -1301,6 +1301,46 @@ export const settingsDict = {
   'settings.providers.page.connect.searchProvidersPlaceholder': '搜索...',
   'settings.providers.page.connect.noProvidersFound': '未找到提供商',
   'settings.providers.page.connect.allProvidersConnected': '所有提供商均已连接。',
+  'settings.providers.page.custom.optionLabel': '其他 / 自定义',
+  'settings.providers.page.custom.title': '自定义提供商',
+  'settings.providers.page.custom.description': '通过指定基础 URL、凭据和模型列表，添加兼容 OpenAI 的提供商。会写入 OpenCode 配置，可像其他提供商一样在聊天中使用。',
+  'settings.providers.page.custom.field.providerID.label': '提供商 ID',
+  'settings.providers.page.custom.field.providerID.placeholder': 'my-provider',
+  'settings.providers.page.custom.field.providerID.info': '小写字母、数字、连字符和下划线。用作 OpenCode 提供商 ID。',
+  'settings.providers.page.custom.field.name.label': '显示名称',
+  'settings.providers.page.custom.field.name.placeholder': '我的提供商',
+  'settings.providers.page.custom.field.name.info': '显示在提供商和模型选择器中。',
+  'settings.providers.page.custom.field.baseURL.label': '基础 URL',
+  'settings.providers.page.custom.field.baseURL.placeholder': 'https://api.example.com/v1',
+  'settings.providers.page.custom.field.baseURL.info': '兼容 OpenAI 的 API 基础 URL。必须以 http:// 或 https:// 开头。',
+  'settings.providers.page.custom.field.apiKey.label': 'API 密钥',
+  'settings.providers.page.custom.field.apiKey.placeholder': 'sk-... 或 {env:VAR_NAME}',
+  'settings.providers.page.custom.field.apiKey.info': '保存在 OpenCode 认证中，而非 OpenChamber。使用 {env:VAR_NAME} 可从环境变量读取密钥。',
+  'settings.providers.page.custom.models.title': '模型',
+  'settings.providers.page.custom.models.idLabel': '模型 ID',
+  'settings.providers.page.custom.models.idPlaceholder': 'gpt-4o',
+  'settings.providers.page.custom.models.nameLabel': '模型名称',
+  'settings.providers.page.custom.models.namePlaceholder': 'GPT-4o',
+  'settings.providers.page.custom.models.add': '添加模型',
+  'settings.providers.page.custom.models.remove': '移除模型',
+  'settings.providers.page.custom.headers.title': '请求头',
+  'settings.providers.page.custom.headers.description': '每次调用可选发送的请求头。',
+  'settings.providers.page.custom.headers.keyLabel': '请求头名称',
+  'settings.providers.page.custom.headers.keyPlaceholder': 'X-Custom-Header',
+  'settings.providers.page.custom.headers.valueLabel': '请求头值',
+  'settings.providers.page.custom.headers.valuePlaceholder': 'value',
+  'settings.providers.page.custom.headers.add': '添加请求头',
+  'settings.providers.page.custom.headers.remove': '移除请求头',
+  'settings.providers.page.custom.actions.back': '返回',
+  'settings.providers.page.custom.actions.save': '保存提供商',
+  'settings.providers.page.custom.error.providerID.required': '提供商 ID 为必填项',
+  'settings.providers.page.custom.error.providerID.format': '请使用小写字母、数字、连字符或下划线',
+  'settings.providers.page.custom.error.providerID.exists': '已连接具有此 ID 的提供商',
+  'settings.providers.page.custom.error.name.required': '显示名称为必填项',
+  'settings.providers.page.custom.error.baseURL.required': '基础 URL 为必填项',
+  'settings.providers.page.custom.error.baseURL.format': '基础 URL 必须以 http:// 或 https:// 开头',
+  'settings.providers.page.custom.error.required': '必填',
+  'settings.providers.page.custom.error.duplicate': '重复',
   'settings.providers.page.auth.title': '认证',
   'settings.providers.page.auth.loadingMethods': '正在加载认证方式...',
   'settings.providers.page.auth.apiKeyLabel': 'API Key',
@@ -1358,6 +1398,8 @@ export const settingsDict = {
   'settings.providers.page.toast.deviceCodeCopyFailed': '复制设备代码失败',
   'settings.providers.page.toast.providerDisconnected': '提供商已断开连接',
   'settings.providers.page.toast.providerDisconnectFailed': '断开提供商连接失败',
+  'settings.providers.page.toast.customProviderSaved': '已连接 {provider}',
+  'settings.providers.page.toast.customProviderSaveFailed': '保存自定义提供商失败',
   'settings.mcp.page.empty.selectServer': '请从侧边栏选择一个 MCP 服务器',
   'settings.mcp.page.empty.addNewOne': '或添加一个新的',
   'settings.mcp.page.header.newServer': '新建 MCP 服务器',
diff --git a/packages/ui/src/lib/i18n/messages/zh-TW.settings.ts b/packages/ui/src/lib/i18n/messages/zh-TW.settings.ts
index 332d0f91..d825d1c1 100644
--- a/packages/ui/src/lib/i18n/messages/zh-TW.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/zh-TW.settings.ts
@@ -1207,6 +1207,46 @@
   'settings.providers.page.connect.searchProvidersPlaceholder': '搜尋...',
   'settings.providers.page.connect.noProvidersFound': '找不到供應商',
   'settings.providers.page.connect.allProvidersConnected': '所有供應商均已連線。',
+  'settings.providers.page.custom.optionLabel': '其他 / 自訂',
+  'settings.providers.page.custom.title': '自訂供應商',
+  'settings.providers.page.custom.description': '透過指定基礎 URL、憑證與模型清單，新增相容 OpenAI 的供應商。會寫入 OpenCode 設定，可像其他供應商一樣在聊天中使用。',
+  'settings.providers.page.custom.field.providerID.label': '供應商 ID',
+  'settings.providers.page.custom.field.providerID.placeholder': 'my-provider',
+  'settings.providers.page.custom.field.providerID.info': '小寫字母、數字、連字號與底線。用作 OpenCode 供應商 ID。',
+  'settings.providers.page.custom.field.name.label': '顯示名稱',
+  'settings.providers.page.custom.field.name.placeholder': '我的供應商',
+  'settings.providers.page.custom.field.name.info': '顯示於供應商與模型選擇器。',
+  'settings.providers.page.custom.field.baseURL.label': '基礎 URL',
+  'settings.providers.page.custom.field.baseURL.placeholder': 'https://api.example.com/v1',
+  'settings.providers.page.custom.field.baseURL.info': '相容 OpenAI 的 API 基礎 URL。必須以 http:// 或 https:// 開頭。',
+  'settings.providers.page.custom.field.apiKey.label': 'API 金鑰',
+  'settings.providers.page.custom.field.apiKey.placeholder': 'sk-... 或 {env:VAR_NAME}',
+  'settings.providers.page.custom.field.apiKey.info': '儲存在 OpenCode 驗證中，而非 OpenChamber。使用 {env:VAR_NAME} 可從環境變數讀取金鑰。',
+  'settings.providers.page.custom.models.title': '模型',
+  'settings.providers.page.custom.models.idLabel': '模型 ID',
+  'settings.providers.page.custom.models.idPlaceholder': 'gpt-4o',
+  'settings.providers.page.custom.models.nameLabel': '模型名稱',
+  'settings.providers.page.custom.models.namePlaceholder': 'GPT-4o',
+  'settings.providers.page.custom.models.add': '新增模型',
+  'settings.providers.page.custom.models.remove': '移除模型',
+  'settings.providers.page.custom.headers.title': '標頭',
+  'settings.providers.page.custom.headers.description': '每次呼叫可選擇傳送的請求標頭。',
+  'settings.providers.page.custom.headers.keyLabel': '標頭名稱',
+  'settings.providers.page.custom.headers.keyPlaceholder': 'X-Custom-Header',
+  'settings.providers.page.custom.headers.valueLabel': '標頭值',
+  'settings.providers.page.custom.headers.valuePlaceholder': 'value',
+  'settings.providers.page.custom.headers.add': '新增標頭',
+  'settings.providers.page.custom.headers.remove': '移除標頭',
+  'settings.providers.page.custom.actions.back': '返回',
+  'settings.providers.page.custom.actions.save': '儲存供應商',
+  'settings.providers.page.custom.error.providerID.required': '供應商 ID 為必填',
+  'settings.providers.page.custom.error.providerID.format': '請使用小寫字母、數字、連字號或底線',
+  'settings.providers.page.custom.error.providerID.exists': '已連線具有此 ID 的供應商',
+  'settings.providers.page.custom.error.name.required': '顯示名稱為必填',
+  'settings.providers.page.custom.error.baseURL.required': '基礎 URL 為必填',
+  'settings.providers.page.custom.error.baseURL.format': '基礎 URL 必須以 http:// 或 https:// 開頭',
+  'settings.providers.page.custom.error.required': '必填',
+  'settings.providers.page.custom.error.duplicate': '重複',
   'settings.providers.page.auth.title': '驗證',
   'settings.providers.page.auth.loadingMethods': '正在載入驗證方式...',
   'settings.providers.page.auth.apiKeyLabel': 'API Key',
@@ -1264,6 +1304,8 @@
   'settings.providers.page.toast.deviceCodeCopyFailed': '複製裝置程式碼失敗',
   'settings.providers.page.toast.providerDisconnected': '供應商已中斷連線',
   'settings.providers.page.toast.providerDisconnectFailed': '中斷供應商連線失敗',
+  'settings.providers.page.toast.customProviderSaved': '已連線 {provider}',
+  'settings.providers.page.toast.customProviderSaveFailed': '無法儲存自訂供應商',
   'settings.mcp.page.empty.selectServer': '請從側邊欄選擇一個 MCP 伺服器',
   'settings.mcp.page.empty.addNewOne': '或新增一個新的',
   'settings.mcp.page.header.newServer': '新建 MCP 伺服器',
diff --git a/packages/ui/src/lib/settings/search.ts b/packages/ui/src/lib/settings/search.ts
index 33db680a..556742bc 100644
--- a/packages/ui/src/lib/settings/search.ts
+++ b/packages/ui/src/lib/settings/search.ts
@@ -754,6 +754,13 @@ const SETTINGS_SEARCH_ITEMS: readonly SettingsSearchItem[] = [
     titleKey: 'settings.providers.page.connect.title',
     keywords: ['add provider', 'connect provider', 'credentials'],
   },
+  {
+    id: 'providers.custom',
+    page: 'providers',
+    titleKey: 'settings.providers.page.custom.title',
+    descriptionKey: 'settings.providers.page.custom.description',
+    keywords: ['other', 'custom', 'openai-compatible', 'base url', 'api key'],
+  },
   {
     id: 'providers.auth',
     page: 'providers',
diff --git a/packages/vscode/src/DOCUMENTATION.md b/packages/vscode/src/DOCUMENTATION.md
index 6b358890..ef6a2432 100644
--- a/packages/vscode/src/DOCUMENTATION.md
+++ b/packages/vscode/src/DOCUMENTATION.md
@@ -61,6 +61,7 @@ The webview CSP permits `blob:` only for `worker-src` so shared UI parsers can r
   - Includes session activity snapshot bridge handler used by webview parity routes (`/api/session-activity`).
   - Includes Zen utility model parity handler used by shared notification settings (`/api/zen/models`).
   - Owns managed OpenCode upgrade status and mutation handlers, including capability reporting, upgrade serialization, and process restart after a successful upgrade.
+  - Provider handlers cover source lookup, disconnect (`DELETE /api/provider/:id/auth`), and custom provider upsert (`PUT /api/provider`).
 
 - `opencode-upgrade-runtime.ts`
   - Owns managed-versus-external capability decisions, latest-version checks, serialized OpenCode self-upgrades, and restart-after-upgrade behavior.
diff --git a/packages/vscode/src/bridge-system-runtime.ts b/packages/vscode/src/bridge-system-runtime.ts
index ffc1bfaf..50a2bfd0 100644
--- a/packages/vscode/src/bridge-system-runtime.ts
+++ b/packages/vscode/src/bridge-system-runtime.ts
@@ -3,7 +3,7 @@ import * as os from 'os';
 import * as path from 'path';
 import * as vscode from 'vscode';
 import { randomUUID } from 'crypto';
-import { removeProviderConfig, getProviderSources } from './opencodeConfig';
+import { removeProviderConfig, getProviderSources, upsertProviderConfig } from './opencodeConfig';
 import { getProviderAuth, removeProviderAuth } from './opencodeAuth';
 import { fetchQuotaForProvider, listConfiguredQuotaProviders } from './quotaProviders';
 import { fetchOpenCodeGoUsage } from './opencodeGoQuota';
@@ -485,6 +485,63 @@ export async function handleSystemBridgeMessage(
       }
     }
 
+    case 'api:provider:upsert': {
+      const {
+        providerID,
+        providerId: providerIdAlias,
+        config,
+        scope,
+        directory,
+      } = (payload || {}) as {
+        providerID?: string;
+        providerId?: string;
+        config?: unknown;
+        scope?: string;
+        directory?: string;
+      };
+      const providerId = (typeof providerID === 'string' && providerID.trim())
+        || (typeof providerIdAlias === 'string' && providerIdAlias.trim())
+        || '';
+      if (!providerId) {
+        return { id, type, success: false, error: 'Provider ID is required' };
+      }
+      if (!config || typeof config !== 'object' || Array.isArray(config)) {
+        return { id, type, success: false, error: 'Provider config is required' };
+      }
+      const normalizedScope = typeof scope === 'string' ? scope : 'user';
+      if (normalizedScope !== 'user' && normalizedScope !== 'project' && normalizedScope !== 'custom') {
+        return { id, type, success: false, error: 'Invalid scope' };
+      }
+      try {
+        const workingDirectory = typeof directory === 'string' && directory.trim().length > 0
+          ? directory.trim()
+          : ctx?.manager?.getWorkingDirectory();
+        const result = upsertProviderConfig(
+          providerId,
+          config,
+          workingDirectory,
+          normalizedScope,
+        );
+        await ctx?.manager?.restart();
+        return {
+          id,
+          type,
+          success: true,
+          data: {
+            success: true,
+            providerId: result.providerId,
+            path: result.path,
+            config: result.config,
+            requiresReload: true,
+            reloadDelayMs: deps.clientReloadDelayMs,
+          },
+        };
+      } catch (error) {
+        const errorMessage = error instanceof Error ? error.message : String(error);
+        return { id, type, success: false, error: errorMessage };
+      }
+    }
+
     case 'api:quota:providers': {
       try {
         const providers = listConfiguredQuotaProviders();
diff --git a/packages/vscode/src/opencodeConfig.ts b/packages/vscode/src/opencodeConfig.ts
index 79a7455d..0116951d 100644
--- a/packages/vscode/src/opencodeConfig.ts
+++ b/packages/vscode/src/opencodeConfig.ts
@@ -2168,6 +2168,153 @@ export const removeProviderConfig = (providerId: string, workingDirectory?: stri
   return true;
 };
 
+const PROVIDER_ID_PATTERN = /^[a-z0-9][a-z0-9-_]*$/;
+const BASE_URL_PATTERN = /^https?:\/\//;
+const OPENAI_COMPATIBLE_NPM = '@ai-sdk/openai-compatible';
+
+export const validateCustomProviderConfig = (providerId: string, config: unknown) => {
+  if (!providerId || typeof providerId !== 'string' || !PROVIDER_ID_PATTERN.test(providerId)) {
+    return { ok: false as const, error: 'Provider ID must match /^[a-z0-9][a-z0-9-_]*$/' };
+  }
+
+  if (!isPlainObject(config)) {
+    return { ok: false as const, error: 'Provider config must be an object' };
+  }
+
+  const name = typeof config.name === 'string' ? config.name.trim() : '';
+  if (!name) {
+    return { ok: false as const, error: 'Provider name is required' };
+  }
+
+  const npm = typeof config.npm === 'string' ? config.npm.trim() : OPENAI_COMPATIBLE_NPM;
+  if (npm !== OPENAI_COMPATIBLE_NPM) {
+    return { ok: false as const, error: `Custom providers must use npm package ${OPENAI_COMPATIBLE_NPM}` };
+  }
+
+  const options = isPlainObject(config.options) ? config.options : null;
+  if (!options) {
+    return { ok: false as const, error: 'Provider options are required' };
+  }
+
+  const baseURL = typeof options.baseURL === 'string' ? options.baseURL.trim() : '';
+  if (!baseURL) {
+    return { ok: false as const, error: 'Base URL is required' };
+  }
+  if (!BASE_URL_PATTERN.test(baseURL)) {
+    return { ok: false as const, error: 'Base URL must start with http:// or https://' };
+  }
+
+  const models = isPlainObject(config.models) ? config.models : null;
+  if (!models || Object.keys(models).length === 0) {
+    return { ok: false as const, error: 'At least one model is required' };
+  }
+
+  const normalizedModels: Record<string, { name: string }> = {};
+  for (const [modelId, modelValue] of Object.entries(models)) {
+    const trimmedId = typeof modelId === 'string' ? modelId.trim() : '';
+    if (!trimmedId) {
+      return { ok: false as const, error: 'Model id is required' };
+    }
+    if (!isPlainObject(modelValue)) {
+      return { ok: false as const, error: `Model "${trimmedId}" must be an object` };
+    }
+    const modelName = typeof modelValue.name === 'string' ? modelValue.name.trim() : '';
+    if (!modelName) {
+      return { ok: false as const, error: `Model "${trimmedId}" requires a name` };
+    }
+    normalizedModels[trimmedId] = { name: modelName };
+  }
+
+  const normalized: Record<string, unknown> = {
+    npm: OPENAI_COMPATIBLE_NPM,
+    name,
+    options: {
+      baseURL,
+    },
+    models: normalizedModels,
+  };
+
+  if (Array.isArray(config.env)) {
+    const env = config.env
+      .filter((entry): entry is string => typeof entry === 'string' && entry.trim().length > 0)
+      .map((entry) => entry.trim());
+    if (env.length > 0) {
+      normalized.env = env;
+    }
+  }
+
+  if (isPlainObject(options.headers)) {
+    const headers: Record<string, string> = {};
+    for (const [headerKey, headerValue] of Object.entries(options.headers)) {
+      if (typeof headerKey !== 'string' || !headerKey.trim()) {
+        continue;
+      }
+      if (typeof headerValue !== 'string' || !headerValue.trim()) {
+        return { ok: false as const, error: `Header "${headerKey}" requires a non-empty value` };
+      }
+      headers[headerKey.trim()] = headerValue.trim();
+    }
+    if (Object.keys(headers).length > 0) {
+      (normalized.options as Record<string, unknown>).headers = headers;
+    }
+  }
+
+  return { ok: true as const, value: { providerId, config: normalized } };
+};
+
+export const upsertProviderConfig = (
+  providerId: string,
+  config: unknown,
+  workingDirectory?: string,
+  scope: 'user' | 'project' | 'custom' = 'user',
+) => {
+  const validated = validateCustomProviderConfig(providerId, config);
+  if (!validated.ok) {
+    const error = new Error(validated.error) as Error & { statusCode?: number };
+    error.statusCode = 400;
+    throw error;
+  }
+
+  const layers = readConfigLayers(workingDirectory);
+  let targetPath: string | null | undefined = layers.paths.userPath;
+
+  if (scope === 'project') {
+    if (!workingDirectory) {
+      throw new Error('Working directory is required for project scope');
+    }
+    targetPath = layers.paths.projectPath ?? targetPath;
+  } else if (scope === 'custom') {
+    if (!layers.paths.customPath) {
+      throw new Error('Custom config path (OPENCODE_CONFIG) is not set');
+    }
+    targetPath = layers.paths.customPath;
+  } else if (scope !== 'user') {
+    throw new Error('Invalid scope');
+  }
+
+  const targetConfig = getConfigForPath(layers, targetPath) as Record<string, unknown>;
+  const providerConfig = isPlainObject(targetConfig.provider)
+    ? { ...(targetConfig.provider as Record<string, unknown>) }
+    : {};
+  providerConfig[validated.value.providerId] = validated.value.config;
+  targetConfig.provider = providerConfig;
+
+  if (Array.isArray(targetConfig.disabled_providers)) {
+    targetConfig.disabled_providers = targetConfig.disabled_providers.filter(
+      (entry) => entry !== validated.value.providerId,
+    );
+  }
+
+  const writePath = targetPath || CONFIG_FILE;
+  writeConfig(targetConfig, writePath);
+
+  return {
+    providerId: validated.value.providerId,
+    path: writePath,
+    config: validated.value.config,
+  };
+};
+
 export const deleteCommand = (commandName: string, workingDirectory?: string) => {
   let deleted = false;
 
diff --git a/packages/vscode/webview/main.tsx b/packages/vscode/webview/main.tsx
index ad081713..601859d9 100644
--- a/packages/vscode/webview/main.tsx
+++ b/packages/vscode/webview/main.tsx
@@ -1118,6 +1118,30 @@ const handleLocalApiRequest = async (input: RequestInfo | URL, url: URL, init: R
     }
   }
 
+  // Handle custom provider upsert: PUT /api/provider
+  if (pathname === '/api/provider' && method === 'PUT') {
+    try {
+      const body = await extractJsonBody(input, init, method);
+      const queryDirectory = url.searchParams.get('directory') || undefined;
+      const data = await sendBridgeMessage('api:provider:upsert', {
+        ...(body && typeof body === 'object' ? body : {}),
+        directory: queryDirectory
+          ?? (body && typeof body === 'object' && typeof body.directory === 'string' ? body.directory : undefined),
+      });
+      if (data && typeof data === 'object' && 'success' in data && (data as { success?: boolean }).success === false) {
+        const message = (data as { error?: string }).error || 'Failed to save provider config';
+        return new Response(JSON.stringify({ error: message }), { status: 400, headers: { 'Content-Type': 'application/json' } });
+      }
+      return new Response(JSON.stringify((data as { data?: unknown })?.data ?? data), {
+        status: 200,
+        headers: { 'Content-Type': 'application/json' },
+      });
+    } catch (error) {
+      const message = error instanceof Error ? error.message : String(error);
+      return new Response(JSON.stringify({ error: message }), { status: 500, headers: { 'Content-Type': 'application/json' } });
+    }
+  }
+
   return null;
 };
 
diff --git a/packages/web/server/lib/opencode/DOCUMENTATION.md b/packages/web/server/lib/opencode/DOCUMENTATION.md
index c57ecb8b..d7936277 100644
--- a/packages/web/server/lib/opencode/DOCUMENTATION.md
+++ b/packages/web/server/lib/opencode/DOCUMENTATION.md
@@ -57,6 +57,12 @@ This module provides OpenCode server integration utilities for the web server ru
 - `AUTH_FILE`: Auth file path constant.
 - `OPENCODE_DATA_DIR`: OpenCode data directory path constant.
 
+## Public exports (providers.js)
+- `getProviderSources(providerId, workingDirectory)`: Resolves which OpenCode config layers define a provider.
+- `upsertProviderConfig(providerId, config, workingDirectory, scope?)`: Validates and writes a custom OpenAI-compatible provider block (`npm`, `name`, `options.baseURL`, `models`, optional `env`/`headers`) into the user/project/custom config layer. Does not store API keys.
+- `validateCustomProviderConfig(providerId, config)`: Structural validation for custom provider payloads (id format, http(s) base URL, models).
+- `removeProviderConfig(providerId, workingDirectory, scope?)`: Removes a provider block from the selected config layer.
+
 ## Public exports (shared.js)
 - `OPENCODE_CONFIG_DIR`, `AGENT_DIR`, `COMMAND_DIR`, `SKILL_DIR`, `CONFIG_FILE`, `CUSTOM_CONFIG_FILE`: Path constants.
 - `AGENT_SCOPE`, `COMMAND_SCOPE`, `SKILL_SCOPE`: Scope constants with USER and PROJECT values.
@@ -82,6 +88,7 @@ This module provides OpenCode server integration utilities for the web server ru
   - `GET /api/opencode/upgrade-status` (returns version availability plus the authoritative `upgrade.supported`, `upgrade.manager`, and `upgrade.reason` capability)
   - `POST /api/opencode/directory`
   - `GET /api/provider/:providerId/source`
+  - `PUT /api/provider` (create/update custom OpenAI-compatible provider config in OpenCode user/project/custom layers; secrets stay in auth via the OpenCode auth API)
   - `DELETE /api/provider/:providerId/auth`
 - Owns lazy auth library loading for provider auth checks/removal.
 - Keeps route behavior independent from composition root; `index.js` now supplies dependencies only.
diff --git a/packages/web/server/lib/opencode/feature-routes-runtime.js b/packages/web/server/lib/opencode/feature-routes-runtime.js
index c0b55e99..0a6dbf8a 100644
--- a/packages/web/server/lib/opencode/feature-routes-runtime.js
+++ b/packages/web/server/lib/opencode/feature-routes-runtime.js
@@ -18,7 +18,7 @@ import { registerPluginRoutes } from './plugin-routes.js';
 import { getNpmInfo, clearCache as clearNpmCache } from './npm-registry.js';
 import { parseNpmSpec, parsePathSpec, isExactSemver } from './plugin-spec.js';
 import { registerOpenCodeRoutes } from './routes.js';
-import { getProviderSources, removeProviderConfig } from './providers.js';
+import { getProviderSources, removeProviderConfig, upsertProviderConfig } from './providers.js';
 import { getAgentSources, getAgentConfig, createAgent, updateAgent, deleteAgent } from './agents.js';
 import { getCommandSources, createCommand, updateCommand, deleteCommand } from './commands.js';
 import { listMcpConfigs, getMcpConfig, createMcpConfig, updateMcpConfig, deleteMcpConfig } from './mcp.js';
@@ -132,6 +132,7 @@ export const createFeatureRoutesRuntime = (dependencies) => {
       resolveProjectDirectory,
       getProviderSources,
       removeProviderConfig,
+      upsertProviderConfig,
       refreshOpenCodeAfterConfigChange,
       buildOpenCodeUrl,
       getOpenCodeAuthHeaders,
diff --git a/packages/web/server/lib/opencode/providers.js b/packages/web/server/lib/opencode/providers.js
index 419cfe59..58809a30 100644
--- a/packages/web/server/lib/opencode/providers.js
+++ b/packages/web/server/lib/opencode/providers.js
@@ -6,6 +6,10 @@ import {
   writeConfig,
 } from './shared.js';
 
+const PROVIDER_ID_PATTERN = /^[a-z0-9][a-z0-9-_]*$/;
+const BASE_URL_PATTERN = /^https?:\/\//;
+const OPENAI_COMPATIBLE_NPM = '@ai-sdk/openai-compatible';
+
 function getProviderSources(providerId, workingDirectory) {
   const layers = readConfigLayers(workingDirectory);
   const { userConfig, projectConfig, customConfig, paths } = layers;
@@ -37,6 +41,150 @@ function getProviderSources(providerId, workingDirectory) {
   };
 }
 
+/**
+ * Validate a custom OpenAI-compatible provider config payload before persistence.
+ * Returns { ok: true, value } or { ok: false, error }.
+ */
+function validateCustomProviderConfig(providerId, config) {
+  if (!providerId || typeof providerId !== 'string' || !PROVIDER_ID_PATTERN.test(providerId)) {
+    return { ok: false, error: 'Provider ID must match /^[a-z0-9][a-z0-9-_]*$/' };
+  }
+
+  if (!isPlainObject(config)) {
+    return { ok: false, error: 'Provider config must be an object' };
+  }
+
+  const name = typeof config.name === 'string' ? config.name.trim() : '';
+  if (!name) {
+    return { ok: false, error: 'Provider name is required' };
+  }
+
+  const npm = typeof config.npm === 'string' ? config.npm.trim() : OPENAI_COMPATIBLE_NPM;
+  if (npm !== OPENAI_COMPATIBLE_NPM) {
+    return { ok: false, error: `Custom providers must use npm package ${OPENAI_COMPATIBLE_NPM}` };
+  }
+
+  const options = isPlainObject(config.options) ? config.options : null;
+  if (!options) {
+    return { ok: false, error: 'Provider options are required' };
+  }
+
+  const baseURL = typeof options.baseURL === 'string' ? options.baseURL.trim() : '';
+  if (!baseURL) {
+    return { ok: false, error: 'Base URL is required' };
+  }
+  if (!BASE_URL_PATTERN.test(baseURL)) {
+    return { ok: false, error: 'Base URL must start with http:// or https://' };
+  }
+
+  const models = isPlainObject(config.models) ? config.models : null;
+  if (!models || Object.keys(models).length === 0) {
+    return { ok: false, error: 'At least one model is required' };
+  }
+
+  const normalizedModels = {};
+  for (const [modelId, modelValue] of Object.entries(models)) {
+    const trimmedId = typeof modelId === 'string' ? modelId.trim() : '';
+    if (!trimmedId) {
+      return { ok: false, error: 'Model id is required' };
+    }
+    if (!isPlainObject(modelValue)) {
+      return { ok: false, error: `Model "${trimmedId}" must be an object` };
+    }
+    const modelName = typeof modelValue.name === 'string' ? modelValue.name.trim() : '';
+    if (!modelName) {
+      return { ok: false, error: `Model "${trimmedId}" requires a name` };
+    }
+    normalizedModels[trimmedId] = { name: modelName };
+  }
+
+  const normalized = {
+    npm: OPENAI_COMPATIBLE_NPM,
+    name,
+    options: {
+      baseURL,
+    },
+    models: normalizedModels,
+  };
+
+  if (Array.isArray(config.env)) {
+    const env = config.env
+      .filter((entry) => typeof entry === 'string' && entry.trim().length > 0)
+      .map((entry) => entry.trim());
+    if (env.length > 0) {
+      normalized.env = env;
+    }
+  }
+
+  if (isPlainObject(options.headers)) {
+    const headers = {};
+    for (const [headerKey, headerValue] of Object.entries(options.headers)) {
+      if (typeof headerKey !== 'string' || !headerKey.trim()) {
+        continue;
+      }
+      if (typeof headerValue !== 'string' || !headerValue.trim()) {
+        return { ok: false, error: `Header "${headerKey}" requires a non-empty value` };
+      }
+      headers[headerKey.trim()] = headerValue.trim();
+    }
+    if (Object.keys(headers).length > 0) {
+      normalized.options.headers = headers;
+    }
+  }
+
+  return { ok: true, value: { providerId, config: normalized } };
+}
+
+/**
+ * Persist (create or update) a custom provider block in OpenCode user/project/custom config.
+ * Does not write secrets — API keys remain in auth.json via the OpenCode auth API.
+ */
+function upsertProviderConfig(providerId, config, workingDirectory, scope = 'user') {
+  const validated = validateCustomProviderConfig(providerId, config);
+  if (!validated.ok) {
+    const error = new Error(validated.error);
+    error.statusCode = 400;
+    throw error;
+  }
+
+  const layers = readConfigLayers(workingDirectory);
+  let targetPath = layers.paths.userPath;
+
+  if (scope === 'project') {
+    if (!workingDirectory) {
+      throw new Error('Working directory is required for project scope');
+    }
+    targetPath = layers.paths.projectPath || targetPath;
+  } else if (scope === 'custom') {
+    if (!layers.paths.customPath) {
+      throw new Error('Custom config path (OPENCODE_CONFIG) is not set');
+    }
+    targetPath = layers.paths.customPath;
+  } else if (scope !== 'user') {
+    throw new Error('Invalid scope');
+  }
+
+  const targetConfig = getConfigForPath(layers, targetPath);
+  const providerConfig = isPlainObject(targetConfig.provider) ? { ...targetConfig.provider } : {};
+  providerConfig[validated.value.providerId] = validated.value.config;
+  targetConfig.provider = providerConfig;
+
+  if (Array.isArray(targetConfig.disabled_providers)) {
+    targetConfig.disabled_providers = targetConfig.disabled_providers.filter(
+      (entry) => entry !== validated.value.providerId,
+    );
+  }
+
+  const writePath = targetPath || CONFIG_FILE;
+  writeConfig(targetConfig, writePath);
+
+  return {
+    providerId: validated.value.providerId,
+    path: writePath,
+    config: validated.value.config,
+  };
+}
+
 function removeProviderConfig(providerId, workingDirectory, scope = 'user') {
   if (!providerId || typeof providerId !== 'string') {
     throw new Error('Provider ID is required');
@@ -93,4 +241,6 @@ function removeProviderConfig(providerId, workingDirectory, scope = 'user') {
 export {
   getProviderSources,
   removeProviderConfig,
+  upsertProviderConfig,
+  validateCustomProviderConfig,
 };
diff --git a/packages/web/server/lib/opencode/providers.test.js b/packages/web/server/lib/opencode/providers.test.js
new file mode 100644
index 00000000..4a4bf9c8
--- /dev/null
+++ b/packages/web/server/lib/opencode/providers.test.js
@@ -0,0 +1,137 @@
+import { afterEach, beforeEach, describe, expect, test } from 'bun:test';
+import fs from 'fs';
+import os from 'os';
+import path from 'path';
+
+import {
+  upsertProviderConfig,
+  validateCustomProviderConfig,
+  getProviderSources,
+  removeProviderConfig,
+} from './providers.js';
+
+let projectDir;
+
+function writeJson(filePath, value) {
+  fs.mkdirSync(path.dirname(filePath), { recursive: true });
+  fs.writeFileSync(filePath, JSON.stringify(value, null, 2), 'utf8');
+}
+
+function readJson(filePath) {
+  return JSON.parse(fs.readFileSync(filePath, 'utf8'));
+}
+
+describe('custom provider config persistence', () => {
+  beforeEach(() => {
+    projectDir = fs.mkdtempSync(path.join(os.tmpdir(), 'openchamber-provider-'));
+  });
+
+  afterEach(() => {
+    fs.rmSync(projectDir, { recursive: true, force: true });
+  });
+
+  test('validateCustomProviderConfig rejects invalid endpoint and credentials shape', () => {
+    expect(validateCustomProviderConfig('Bad Id', {
+      name: 'X',
+      options: { baseURL: 'https://api.example.com' },
+      models: { m: { name: 'M' } },
+    }).ok).toBe(false);
+
+    expect(validateCustomProviderConfig('ok', {
+      name: 'X',
+      options: { baseURL: 'ftp://api.example.com' },
+      models: { m: { name: 'M' } },
+    }).error).toContain('http://');
+
+    expect(validateCustomProviderConfig('ok', {
+      name: 'X',
+      options: { baseURL: 'https://api.example.com' },
+      models: {},
+    }).ok).toBe(false);
+  });
+
+  test('upsertProviderConfig writes and round-trips project config', () => {
+    const result = upsertProviderConfig('campus-llm', {
+      name: 'Campus LLM',
+      npm: '@ai-sdk/openai-compatible',
+      options: {
+        baseURL: 'https://llm.example.edu/v1',
+        headers: { 'X-Campus': '1' },
+      },
+      models: {
+        'fast-model': { name: 'Fast' },
+      },
+      env: ['CAMPUS_KEY'],
+    }, projectDir, 'project');
+
+    expect(result.providerId).toBe('campus-llm');
+    expect(fs.existsSync(result.path)).toBe(true);
+    expect(result.path.startsWith(projectDir)).toBe(true);
+
+    const written = readJson(result.path);
+    expect(written.provider['campus-llm']).toEqual({
+      npm: '@ai-sdk/openai-compatible',
+      name: 'Campus LLM',
+      env: ['CAMPUS_KEY'],
+      options: {
+        baseURL: 'https://llm.example.edu/v1',
+        headers: { 'X-Campus': '1' },
+      },
+      models: {
+        'fast-model': { name: 'Fast' },
+      },
+    });
+
+    const sources = getProviderSources('campus-llm', projectDir);
+    expect(sources.sources.project.exists).toBe(true);
+    expect(sources.sources.project.path).toBe(result.path);
+  });
+
+  test('upsertProviderConfig updates existing entry and clears disabled_providers', () => {
+    const configPath = path.join(projectDir, 'opencode.json');
+    writeJson(configPath, {
+      provider: {
+        'campus-llm': {
+          npm: '@ai-sdk/openai-compatible',
+          name: 'Old',
+          options: { baseURL: 'https://old.example.edu/v1' },
+          models: { a: { name: 'A' } },
+        },
+      },
+      disabled_providers: ['campus-llm', 'other'],
+    });
+
+    upsertProviderConfig('campus-llm', {
+      name: 'Campus LLM',
+      options: { baseURL: 'https://llm.example.edu/v1' },
+      models: { b: { name: 'B' } },
+    }, projectDir, 'project');
+
+    const written = readJson(configPath);
+    expect(written.provider['campus-llm'].name).toBe('Campus LLM');
+    expect(written.provider['campus-llm'].models).toEqual({ b: { name: 'B' } });
+    expect(written.disabled_providers).toEqual(['other']);
+  });
+
+  test('upsert then remove restores absence', () => {
+    upsertProviderConfig('temp-provider', {
+      name: 'Temp',
+      options: { baseURL: 'https://api.example.com/v1' },
+      models: { m: { name: 'M' } },
+    }, projectDir, 'project');
+
+    expect(getProviderSources('temp-provider', projectDir).sources.project.exists).toBe(true);
+    expect(removeProviderConfig('temp-provider', projectDir, 'project')).toBe(true);
+    expect(getProviderSources('temp-provider', projectDir).sources.project.exists).toBe(false);
+  });
+
+  test('failed validation does not write config', () => {
+    const configPath = path.join(projectDir, 'opencode.json');
+    expect(() => upsertProviderConfig('ok', {
+      name: 'X',
+      options: { baseURL: 'not-a-url' },
+      models: { m: { name: 'M' } },
+    }, projectDir, 'project')).toThrow(/Base URL/);
+    expect(fs.existsSync(configPath)).toBe(false);
+  });
+});
diff --git a/packages/web/server/lib/opencode/routes.js b/packages/web/server/lib/opencode/routes.js
index b78b550c..b1128f64 100644
--- a/packages/web/server/lib/opencode/routes.js
+++ b/packages/web/server/lib/opencode/routes.js
@@ -18,6 +18,7 @@ export const registerOpenCodeRoutes = (app, dependencies) => {
     resolveProjectDirectory,
     getProviderSources,
     removeProviderConfig,
+    upsertProviderConfig,
     refreshOpenCodeAfterConfigChange,
     buildOpenCodeUrl,
     getOpenCodeAuthHeaders,
@@ -443,6 +444,62 @@ export const registerOpenCodeRoutes = (app, dependencies) => {
     }
   });
 
+  app.put('/api/provider', async (req, res) => {
+    try {
+      const providerID = typeof req.body?.providerID === 'string'
+        ? req.body.providerID.trim()
+        : (typeof req.body?.providerId === 'string' ? req.body.providerId.trim() : '');
+      const config = req.body?.config;
+      const scope = typeof req.body?.scope === 'string' ? req.body.scope : 'user';
+
+      if (!providerID) {
+        return res.status(400).json({ error: 'Provider ID is required' });
+      }
+      if (!config || typeof config !== 'object' || Array.isArray(config)) {
+        return res.status(400).json({ error: 'Provider config is required' });
+      }
+      if (scope !== 'user' && scope !== 'project' && scope !== 'custom') {
+        return res.status(400).json({ error: 'Invalid scope' });
+      }
+
+      const headerDirectory = typeof req.get === 'function' ? req.get('x-opencode-directory') : null;
+      const queryDirectory = Array.isArray(req.query?.directory)
+        ? req.query.directory[0]
+        : req.query?.directory;
+      const requestedDirectory = headerDirectory || queryDirectory || null;
+
+      let directory = null;
+      if (scope === 'project' || requestedDirectory) {
+        const resolved = await resolveProjectDirectory(req);
+        if (!resolved.directory) {
+          return res.status(400).json({ error: resolved.error || 'Working directory is required' });
+        }
+        directory = resolved.directory;
+      } else {
+        const resolved = await resolveProjectDirectory(req);
+        if (resolved.directory) {
+          directory = resolved.directory;
+        }
+      }
+
+      const result = upsertProviderConfig(providerID, config, directory, scope);
+      await refreshOpenCodeAfterConfigChange(`provider ${providerID} upserted (${scope})`);
+
+      return res.json({
+        success: true,
+        providerId: result.providerId,
+        path: result.path,
+        config: result.config,
+        requiresReload: true,
+        reloadDelayMs: clientReloadDelayMs,
+      });
+    } catch (error) {
+      const status = typeof error?.statusCode === 'number' ? error.statusCode : 500;
+      console.error('Failed to upsert provider config:', error);
+      return res.status(status).json({ error: error.message || 'Failed to save provider config' });
+    }
+  });
+
   app.delete('/api/provider/:providerId/auth', async (req, res) => {
     try {
       const { providerId } = req.params;