fix(server): show Implement button more reliably for Claude plan mode

apps/server/src/provider/Layers/ClaudeAdapter.ts

@@ -117,6 +117,7 @@ interface ClaudeTurnState {
   readonly assistantTextBlocks: Map<number, AssistantTextBlockState>;
   readonly assistantTextBlockOrder: Array<AssistantTextBlockState>;
   readonly capturedProposedPlanKeys: Set<string>;
+  readonly interactionMode: "plan" | "default";
   nextSyntheticAssistantBlockIndex: number;
 }
 
@@ -173,6 +174,7 @@ interface ClaudeSessionContext {
   lastKnownTokenUsage: ThreadTokenUsageSnapshot | undefined;
   lastAssistantUuid: string | undefined;
   lastThreadStartedId: string | undefined;
+  currentInteractionMode: "plan" | "default";
   stopped: boolean;
 }
 
@@ -785,6 +787,49 @@ function extractExitPlanModePlan(value: unknown): string | undefined {
     : undefined;
 }
 
+function looksLikePlan(text: string): boolean {
+  const trimmed = text.trim();
+
+  if (trimmed.length < 200) {
+    return false;
+  }
+
+  const headingMatch = /^#{1,4} \S/m.test(trimmed);
+  const orderedListMatch = /^\s*\d+\.\s+\S/m.test(trimmed);
+  const bulletedListMatch = /^\s*[-*]\s+\S/m.test(trimmed);
+
+  if (!headingMatch && !orderedListMatch && !bulletedListMatch) {
+    return false;
+  }
+
+  const firstLineChars = trimmed.substring(0, 120).replace(/^#+\s*/, "");
+  const refusalStems = [
+    /^i can't/i,
+    /^i cannot/i,
+    /^i'm not able/i,
+    /^i am unable/i,
+    /^i don't have enough/i,
+    /^could you clarify/i,
+    /^can you clarify/i,
+    /^before i /i,
+    /^to help you, i need/i,
+  ];
+
+  if (refusalStems.some((stem) => stem.test(firstLineChars))) {
+    return false;
+  }
+
+  const orderedListCount = (trimmed.match(/^\s*\d+\.\s+\S/gm) || []).length;
+  const bulletedListCount = (trimmed.match(/^\s*[-*]\s+\S/gm) || []).length;
+  const totalListItems = orderedListCount + bulletedListCount;
+
+  const planHeadingMatch = /^#{1,4} [^\n]*(?:plan|approach|steps?|implementation|proposal)/i.test(
+    trimmed,
+  );
+
+  return totalListItems >= 3 || planHeadingMatch;
+}
+
 function exitPlanCaptureKey(input: {
   readonly toolUseId?: string | undefined;
   readonly planMarkdown: string;
@@ -1359,7 +1404,10 @@ export const makeClaudeAdapter = Effect.fn("makeClaudeAdapter")(function* (
     input: {
       readonly planMarkdown: string;
       readonly toolUseId?: string | undefined;
-      readonly rawSource: "claude.sdk.message" | "claude.sdk.permission";
+      readonly rawSource:
+        | "claude.sdk.message"
+        | "claude.sdk.permission"
+        | "claude.sdk.text-fallback";
       readonly rawMethod: string;
       readonly rawPayload: unknown;
     },
@@ -1543,6 +1591,35 @@ export const makeClaudeAdapter = Effect.fn("makeClaudeAdapter")(function* (
       });
     }
 
+    if (
+      turnState.interactionMode === "plan" &&
+      turnState.capturedProposedPlanKeys.size === 0 &&
+      context.pendingUserInputs.size === 0 &&
+      status === "completed" &&
+      result?.subtype === "success"
+    ) {
+      let lastNonEmptyBlock: AssistantTextBlockState | undefined;
+      for (let i = turnState.assistantTextBlockOrder.length - 1; i >= 0; i--) {
+        const block = turnState.assistantTextBlockOrder[i];
+        if (!block) {
+          continue;
+        }
+        if (block.fallbackText.trim().length > 0) {
+          lastNonEmptyBlock = block;
+          break;
+        }
+      }
+
+      if (lastNonEmptyBlock && looksLikePlan(lastNonEmptyBlock.fallbackText)) {
+        yield* emitProposedPlanCompleted(context, {
+          planMarkdown: lastNonEmptyBlock.fallbackText,
+          rawSource: "claude.sdk.text-fallback",
+          rawMethod: "claude/text-fallback",
+          rawPayload: result,
+        });
+      }
+    }
+
     const stamp = yield* makeEventStamp();
     yield* offerRuntimeEvent({
       type: "turn.completed",
@@ -1956,6 +2033,7 @@ export const makeClaudeAdapter = Effect.fn("makeClaudeAdapter")(function* (
         assistantTextBlocks: new Map(),
         assistantTextBlockOrder: [],
         capturedProposedPlanKeys: new Set(),
+        interactionMode: "default",
         nextSyntheticAssistantBlockIndex: -1,
       };
       context.session = {
@@ -2973,6 +3051,7 @@ export const makeClaudeAdapter = Effect.fn("makeClaudeAdapter")(function* (
         lastKnownTokenUsage: undefined,
         lastAssistantUuid: resumeState?.resumeSessionAt,
         lastThreadStartedId: undefined,
+        currentInteractionMode: permissionMode === "plan" ? "plan" : "default",
         stopped: false,
       };
       yield* Ref.set(contextRef, context);
@@ -3085,21 +3164,25 @@ export const makeClaudeAdapter = Effect.fn("makeClaudeAdapter")(function* (
         try: () => context.query.setPermissionMode("plan"),
         catch: (cause) => toRequestError(input.threadId, "turn/setPermissionMode", cause),
       });
+      context.currentInteractionMode = "plan";
     } else if (input.interactionMode === "default") {
       yield* Effect.tryPromise({
         try: () => context.query.setPermissionMode(context.basePermissionMode ?? "default"),
         catch: (cause) => toRequestError(input.threadId, "turn/setPermissionMode", cause),
       });
+      context.currentInteractionMode = "default";
     }
 
     const turnId = TurnId.make(yield* Random.nextUUIDv4);
+    const resolvedInteractionMode = context.currentInteractionMode;
     const turnState: ClaudeTurnState = {
       turnId,
       startedAt: yield* nowIso,
       items: [],
       assistantTextBlocks: new Map(),
       assistantTextBlockOrder: [],
       capturedProposedPlanKeys: new Set(),
+      interactionMode: resolvedInteractionMode,
       nextSyntheticAssistantBlockIndex: -1,
     };
 

packages/contracts/src/providerRuntime.ts

@@ -24,6 +24,7 @@ const RuntimeEventRawSource = Schema.Union([
   Schema.Literal("codex.eventmsg"),
   Schema.Literal("claude.sdk.message"),
   Schema.Literal("claude.sdk.permission"),
+  Schema.Literal("claude.sdk.text-fallback"),
   Schema.Literal("codex.sdk.thread-event"),
   Schema.Literal("opencode.sdk.event"),
   Schema.Literal("acp.jsonrpc"),