fix(builtin): disable tools during continue/retry to force frontmatter output

Agent was using all continue turns to keep calling tools instead of
outputting the required frontmatter. Now continue runs with noTools=true,
forcing LLM to emit text-only response.

Also supports null tools in chatCompletionWithTools to omit tools from
the API request entirely.

package.json

@@ -9,7 +9,7 @@
     "check": "bunx tsc --build && biome check . && bash scripts/lint-log-tags.sh",
     "typecheck": "bunx tsc --build",
     "format": "biome format --write .",
-    "test": "bun run --filter '*' test",
+    "test": "bun run --filter './packages/*' test",
     "changeset": "bunx changeset",
     "version": "bunx changeset version",
     "release": "bun run build && bun test && node scripts/publish-all.mjs"

packages/workflow-agent-builtin/src/agent.ts

@@ -66,6 +66,7 @@ async function runBuiltinWithMessages(
   session: SessionRecord,
   store: Store,
   maxTurns: number,
+  noTools: boolean,
 ): Promise<AgentRunResult> {
   const loopResult = await runBuiltinLoop({
     provider,
@@ -74,6 +75,7 @@ async function runBuiltinWithMessages(
     maxTurns,
     storageRoot,
     sessionId: session.sessionId,
+    noTools,
   });
 
   session.messages = loopResult.messages;
@@ -119,6 +121,7 @@ async function runBuiltin(ctx: AgentContext): Promise<AgentRunResult> {
     session,
     ctx.store,
     BUILTIN_MAX_TURNS,
+    false,
   );
 }
 
@@ -141,6 +144,7 @@ async function continueBuiltin(
     session,
     store,
     BUILTIN_CONTINUE_MAX_TURNS,
+    true,
   );
 }
 

packages/workflow-agent-builtin/src/llm/llm.ts

@@ -96,8 +96,17 @@ function serializeMessage(message: ChatMessage): Record<string, unknown> {
 export async function chatCompletionWithTools(
   provider: ResolvedLlmProvider,
   messages: ChatMessage[],
-  tools: OpenAiToolDefinition[],
+  tools: OpenAiToolDefinition[] | null,
 ): Promise<LlmAssistantResponse> {
+  const body: Record<string, unknown> = {
+    model: provider.model,
+    messages: messages.map(serializeMessage),
+  };
+  if (tools !== null && tools.length > 0) {
+    body.tools = tools;
+    body.tool_choice = "auto";
+  }
+
   let response: Response;
   try {
     response = await fetch(chatUrl(provider.baseUrl), {
@@ -106,12 +115,7 @@ export async function chatCompletionWithTools(
         Authorization: `Bearer ${provider.apiKey}`,
         "Content-Type": "application/json",
       },
-      body: JSON.stringify({
-        model: provider.model,
-        messages: messages.map(serializeMessage),
-        tools,
-        tool_choice: "auto",
-      }),
+      body: JSON.stringify(body),
     });
   } catch (cause) {
     const message = cause instanceof Error ? cause.message : String(cause);

packages/workflow-agent-builtin/src/loop.ts

@@ -23,6 +23,8 @@ export type RunBuiltinLoopOptions = {
   maxTurns: number;
   storageRoot: string;
   sessionId: string;
+  /** When true, do not provide tools — force LLM to emit text only. */
+  noTools: boolean;
 };
 
 export type RunBuiltinLoopResult = {
@@ -73,13 +75,17 @@ export async function runBuiltinLoop(
   options: RunBuiltinLoopOptions,
 ): Promise<RunBuiltinLoopResult> {
   const messages = [...options.messages];
-  const openAiTools = builtinToolsToOpenAi(getBuiltinTools());
+  const openAiTools = options.noTools ? [] : builtinToolsToOpenAi(getBuiltinTools());
   let finalText = "";
   let turnCount = 0;
 
   for (let turn = 0; turn < options.maxTurns; turn++) {
     log("8K2M4N7P", `builtin loop turn ${turn + 1}/${options.maxTurns}`);
-    const response = await chatCompletionWithTools(options.provider, messages, openAiTools);
+    const response = await chatCompletionWithTools(
+      options.provider,
+      messages,
+      openAiTools.length > 0 ? openAiTools : null,
+    );
 
     const assistantMessage: ChatMessage = {
       role: "assistant",