feat: expand slash-command goals from command templates

Resolves armed slash-command objectives from authoritative templates before dispatch
Applies OpenCode argument expansion for goal metadata in UI and scheduled tasks
Falls back to the raw invocation when command details are unavailable

packages/ui/src/lib/opencode/client.ts

@@ -1580,9 +1580,10 @@ class OpencodeService {
     }));
   }
 
-  async listCommandsWithDetails(): Promise<Array<{ name: string; description?: string; agent?: string; model?: string; source?: string; template?: string }>> {
+  async listCommandsWithDetails(directory?: string | null): Promise<Array<{ name: string; description?: string; agent?: string; model?: string; source?: string; template?: string }>> {
+    const requestDirectory = this.normalizeCandidatePath(directory ?? null) ?? this.currentDirectory;
     const response = await this.client.command.list(
-      this.currentDirectory ? { directory: this.currentDirectory } : undefined
+      requestDirectory ? { directory: requestDirectory } : undefined
     );
     const commands = unwrapSdkData(response, 'command.list');
     // Return full command details including template

packages/ui/src/sync/session-ui-store.test.js

@@ -3,7 +3,7 @@ import { opencodeClient } from '@/lib/opencode/client';
 import { useProjectsStore } from '@/stores/useProjectsStore';
 import { useDirectoryStore } from '@/stores/useDirectoryStore';
 import { useSessionWorktreeStore } from './session-worktree-store';
-import { routeMessage, useSessionUIStore } from './session-ui-store';
+import { expandSlashCommandGoalObjective, routeMessage, useSessionUIStore } from './session-ui-store';
 import { setActionRefs, setOptimisticRefs } from './session-actions';
 import { useSkillsStore } from '@/stores/useSkillsStore';
 import { useCommandsStore } from '@/stores/useCommandsStore';
@@ -228,6 +228,31 @@ describe('routeMessage directory scoping', () => {
   });
 });
 
+describe('slash-command goal objectives', () => {
+  test('expands every $ARGUMENTS reference from the authoritative command template', () => {
+    expect(expandSlashCommandGoalObjective('/issue--to-pr LIN-123 --draft', [{
+      name: 'issue--to-pr',
+      template: 'Run the issue pipeline for $ARGUMENTS. Verify $ARGUMENTS is represented by the PR.',
+    }])).toBe('Run the issue pipeline for LIN-123 --draft. Verify LIN-123 --draft is represented by the PR.');
+  });
+
+  test('keeps the invocation when the command template is unavailable', () => {
+    expect(expandSlashCommandGoalObjective('/issue--to-pr LIN-123', [{ name: 'issue--to-pr' }]))
+      .toBe('/issue--to-pr LIN-123');
+  });
+
+  test('matches OpenCode positional and implicit argument expansion', () => {
+    expect(expandSlashCommandGoalObjective('/move "src old" dist extra', [{
+      name: 'move',
+      template: 'Move $1 to $2',
+    }])).toBe('Move src old to dist extra');
+    expect(expandSlashCommandGoalObjective('/review auth module', [{
+      name: 'review',
+      template: 'Review the requested scope.',
+    }])).toBe('Review the requested scope.\n\nauth module');
+  });
+});
+
 describe('runtime worktree topology', () => {
   test('restores independent in-memory maps across A -> B -> A', () => {
     const topologyA = new Map([['/repo', [{ path: '/repo/a', branch: 'a' }]]]);

packages/ui/src/sync/session-ui-store.ts

@@ -73,6 +73,34 @@ import { rememberRuntimeLiveStatus } from "./runtime-live-memory"
 
 export type { AttachedFile }
 
+type GoalCommand = { name: string; template?: string }
+
+export function expandSlashCommandGoalObjective(content: string, commands: GoalCommand[]): string {
+  if (!content.startsWith("/")) return content
+  const [head, ...tail] = content.split(" ")
+  const command = commands.find((candidate) => candidate.name === head.slice(1))
+  if (!command?.template?.trim()) return content
+  const argumentsText = tail.join(" ")
+  if (command.template.includes("$ARGUMENTS")) {
+    return command.template.replaceAll("$ARGUMENTS", argumentsText)
+  }
+
+  const positions = [...command.template.matchAll(/\$(\d+)/g)].map((match) => Number(match[1]))
+  if (positions.length > 0) {
+    const parsedArguments = [...argumentsText.matchAll(/"([^"]*)"|'([^']*)'|(\S+)/g)]
+      .map((match) => match[1] ?? match[2] ?? match[3] ?? "")
+    const lastPosition = Math.max(...positions)
+    return command.template.replace(/\$(\d+)/g, (_match, value: string) => {
+      const position = Number(value)
+      return position === lastPosition
+        ? parsedArguments.slice(position - 1).join(" ")
+        : (parsedArguments[position - 1] ?? "")
+    })
+  }
+
+  return argumentsText ? `${command.template}\n\n${argumentsText}` : command.template
+}
+
 // ---------------------------------------------------------------------------
 // Send routing — shell mode, slash commands, or normal prompt
 // ---------------------------------------------------------------------------
@@ -1052,15 +1080,33 @@ export const useSessionUIStore = create<SessionUIState>()((set, get) => ({
       )
       additionalParts = [...(additionalParts ?? []), { text: goalIntro, synthetic: true }]
     }
-    const applyArmedGoal = (goalSessionId: string, goalDirectory: string | null | undefined) => {
+    const applyArmedGoal = async (goalSessionId: string, goalDirectory: string | null | undefined) => {
       if (!goalArmed) return
       const uiState = useUIStore.getState()
       const tokenBudget = uiState.sessionGoalDefaultBudgetEnabled ? uiState.sessionGoalDefaultBudget : null
-      const objective = goalArm.objectiveOverride?.trim() || content
-      void setSessionGoal(goalSessionId, goalDirectory ?? undefined, { objective, tokenBudget }, null)
-        .catch((error) => {
-          console.warn("[session-ui-store] failed to set goal from armed send", error)
-        })
+      let objective = goalArm.objectiveOverride?.trim() || content
+      if (!goalArm.objectiveOverride && content.startsWith("/")) {
+        const directoryCommands = getDirectoryState(goalDirectory ?? undefined)?.command ?? []
+        const storedCommands = useCommandsStore.getState().commands
+        const knownCommands = [...directoryCommands, ...storedCommands]
+        objective = expandSlashCommandGoalObjective(content, knownCommands)
+        if (objective === content) {
+          try {
+            objective = expandSlashCommandGoalObjective(
+              content,
+              await opencodeClient.listCommandsWithDetails(goalDirectory),
+            )
+          } catch {
+            // Command dispatch remains authoritative; raw invocation is a safe objective fallback.
+          }
+        }
+      }
+      try {
+        await setSessionGoal(goalSessionId, goalDirectory ?? undefined, { objective, tokenBudget }, null)
+      } catch (error) {
+        useSessionGoalArmStore.getState().setArmed(true, goalArm.objectiveOverride)
+        throw error
+      }
     }
 
     // ---- New session from draft ----
@@ -1088,6 +1134,7 @@ export const useSessionUIStore = create<SessionUIState>()((set, get) => ({
         filename: a.filename,
       }))
 
+      await applyArmedGoal(createdDraftSession.sessionId, createdDraftSession.directory)
       await routeMessage({
         sessionId: createdDraftSession.sessionId,
         directory: createdDraftSession.directory,
@@ -1111,7 +1158,6 @@ export const useSessionUIStore = create<SessionUIState>()((set, get) => ({
           })),
         })),
       })
-      applyArmedGoal(createdDraftSession.sessionId, createdDraftSession.directory)
       return
     }
 
@@ -1168,6 +1214,9 @@ export const useSessionUIStore = create<SessionUIState>()((set, get) => ({
       filename: a.filename,
     }))
 
+    if (targetSessionId) {
+      await applyArmedGoal(targetSessionId, currentSessionDirectory)
+    }
     await routeMessage({
       sessionId: targetSessionId || "",
       directory: currentSessionDirectory,
@@ -1191,9 +1240,6 @@ export const useSessionUIStore = create<SessionUIState>()((set, get) => ({
         })),
       })),
     })
-    if (targetSessionId) {
-      applyArmedGoal(targetSessionId, currentSessionDirectory)
-    }
   },
 
   // ---------------------------------------------------------------------------