Adjust for unlimited plan option

packages/web/server/lib/quota/DOCUMENTATION.md

@@ -106,6 +106,16 @@ completion quota are intentionally omitted. Keep
 `packages/web/server/lib/quota/providers/copilot.js` and
 `packages/vscode/src/quotaProviders.ts` in sync.
 
+The `/copilot_internal/user` endpoint is undocumented; its quota semantics mirror
+what `microsoft/vscode-copilot-chat` consumes (`CopilotUserQuotaInfo`). Each
+snapshot carries `entitlement`, `remaining`, `unlimited`, and
+`percent_remaining`. Providers must honor these rules:
+
+- `unlimited: true` renders a percent-less window with an "Unlimited" value label.
+- Percent math requires a positive `entitlement`; entitlements of `0`, `-1`, or null are unusable.
+- When entitlement/remaining are unusable, fall back to `100 - percent_remaining`.
+- Snapshots other than `premium_interactions` (legacy annual plans) yield zero windows.
+
 ## Notes for contributors
 - Keep provider IDs stable; clients use them directly.
 - Avoid adding alias-based dispatch in `fetchQuotaForProvider`; dispatch currently expects exact provider IDs.

packages/web/server/lib/quota/providers/copilot.js

@@ -13,14 +13,35 @@ const buildCopilotWindows = (payload) => {
   const resetAt = toTimestamp(payload?.quota_reset_date);
   const windows = {};
 
+  // Mirrors the quota semantics of microsoft/vscode-copilot-chat
+  // (CopilotUserQuotaInfo): each snapshot carries entitlement, remaining,
+  // unlimited, and percent_remaining. Unlimited plans report no usable
+  // entitlement; percent_remaining is a server-computed fallback.
   const addWindow = (label, snapshot) => {
     if (!snapshot) return;
+
+    if (snapshot.unlimited === true) {
+      windows[label] = toUsageWindow({
+        usedPercent: null,
+        windowSeconds: null,
+        resetAt,
+        valueLabel: 'Unlimited'
+      });
+      return;
+    }
+
     const entitlement = toNumber(snapshot.entitlement);
     const remaining = toNumber(snapshot.remaining);
-    const usedPercent = entitlement && remaining !== null
-      ? Math.max(0, 100 - (remaining / entitlement) * 100)
+    let usedPercent = entitlement !== null && entitlement > 0 && remaining !== null
+      ? Math.min(100, Math.max(0, 100 - (remaining / entitlement) * 100))
       : null;
-    const valueLabel = entitlement !== null && remaining !== null
+    if (usedPercent === null) {
+      const percentRemaining = toNumber(snapshot.percent_remaining);
+      if (percentRemaining !== null) {
+        usedPercent = Math.min(100, Math.max(0, 100 - percentRemaining));
+      }
+    }
+    const valueLabel = entitlement !== null && entitlement > 0 && remaining !== null
       ? `${remaining.toFixed(0)} / ${entitlement.toFixed(0)} left`
       : null;
     windows[label] = toUsageWindow({
@@ -141,17 +162,12 @@ export const fetchQuotaAddon = async () => {
     }
 
     const payload = await response.json();
-    const windows = buildCopilotWindows(payload);
-    const premium = windows.premium_interactions
-      ? { premium_interactions: windows.premium_interactions }
-      : windows;
-
     return buildResult({
       providerId: providerIdAddon,
       providerName: providerNameAddon,
       ok: true,
       configured: true,
-      usage: { windows: premium }
+      usage: { windows: buildCopilotWindows(payload) }
     });
   } catch (error) {
     return buildResult({

packages/web/server/lib/quota/providers/copilot.test.js

@@ -19,10 +19,10 @@ const payload = {
   },
 };
 
-const mockResponse = () => ({
+const mockResponse = (body = payload) => ({
   ok: true,
   status: 200,
-  json: async () => payload,
+  json: async () => body,
 });
 
 describe('GitHub Copilot quota provider', () => {
@@ -39,4 +39,40 @@ describe('GitHub Copilot quota provider', () => {
     expect(result.usage.windows.premium_interactions.usedPercent).toBe(25);
     expect(result.usage.windows.premium_interactions.valueLabel).toBe('225 / 300 left');
   });
+
+  it.each([
+    ['primary provider', fetchQuota],
+    ['add-on provider', fetchQuotaAddon],
+  ])('reports unlimited plans without a percent for the %s', async (_name, fetchProviderQuota) => {
+    vi.stubGlobal('fetch', vi.fn().mockResolvedValue(mockResponse({
+      quota_reset_date: '2026-09-01T00:00:00Z',
+      quota_snapshots: {
+        premium_interactions: { unlimited: true, entitlement: -1, remaining: -1 },
+      },
+    })));
+
+    const result = await fetchProviderQuota();
+
+    expect(result.ok).toBe(true);
+    expect(result.usage.windows.premium_interactions.usedPercent).toBeNull();
+    expect(result.usage.windows.premium_interactions.valueLabel).toBe('Unlimited');
+  });
+
+  it.each([
+    ['primary provider', fetchQuota],
+    ['add-on provider', fetchQuotaAddon],
+  ])('falls back to percent_remaining when entitlement is unusable for the %s', async (_name, fetchProviderQuota) => {
+    vi.stubGlobal('fetch', vi.fn().mockResolvedValue(mockResponse({
+      quota_reset_date: '2026-09-01T00:00:00Z',
+      quota_snapshots: {
+        premium_interactions: { entitlement: 0, remaining: 0, percent_remaining: 75.5 },
+      },
+    })));
+
+    const result = await fetchProviderQuota();
+
+    expect(result.ok).toBe(true);
+    expect(result.usage.windows.premium_interactions.usedPercent).toBeCloseTo(24.5);
+    expect(result.usage.windows.premium_interactions.valueLabel ?? null).toBeNull();
+  });
 });