fix(btw): omit empty tool arrays for side questions (#64219) (thanks @ngutman) (#64219)

CHANGELOG.md

@@ -89,6 +89,7 @@ Docs: https://docs.openclaw.ai
 - iMessage (imsg): strip an accidental protobuf length-delimited UTF-8 field wrapper from inbound `text` and `reply_to_text` when it fully consumes the field, fixing leading garbage before the real message. (#63868) Thanks @neeravmakwana.
 - Gateway/pairing: fail closed for paired device records that have no device tokens, and reject pairing approvals whose requested scopes do not match the requested device roles.
 - ACP/gateway chat: classify lifecycle errors before forwarding them to ACP clients so refusals use ACP's refusal stop reason while transient backend errors continue to finish as normal turns.
+- Commands/btw: keep tool-less side questions from sending injected empty `tools` arrays on strict OpenAI-compatible providers, so `/btw` continues working after prior tool-call history. (#64219) Thanks @ngutman.
 
 ## 2026.4.9
 

src/agents/btw.test.ts

@@ -297,6 +297,21 @@ describe("runBtwSideQuestion", () => {
     expect(result).toEqual({ text: "Final answer." });
   });
 
+  it("strips injected empty tools arrays from BTW payloads before sending", async () => {
+    mockDoneAnswer("Final answer.");
+
+    await runSideQuestion();
+
+    const [, , options] = streamSimpleMock.mock.calls[0] ?? [];
+    const onPayload = (options as { onPayload?: (payload: unknown) => void })?.onPayload;
+    const payloadWithEmptyTools = { messages: [], tools: [] as unknown[] };
+
+    const result = onPayload?.(payloadWithEmptyTools);
+
+    expect(payloadWithEmptyTools).not.toHaveProperty("tools");
+    expect(result).toBeUndefined();
+  });
+
   it("forces provider reasoning off even when the session think level is adaptive", async () => {
     streamSimpleMock.mockImplementation((_model, _input, options?: { reasoning?: unknown }) => {
       return options?.reasoning === undefined

src/agents/btw.ts

@@ -21,6 +21,7 @@ import { ensureOpenClawModelsJson } from "./models-config.js";
 import { EmbeddedBlockChunker, type BlockReplyChunking } from "./pi-embedded-block-chunker.js";
 import { resolveModelWithRegistry } from "./pi-embedded-runner/model.js";
 import { getActiveEmbeddedRunSnapshot } from "./pi-embedded-runner/runs.js";
+import { streamWithPayloadPatch } from "./pi-embedded-runner/stream-payload-utils.js";
 import { discoverAuthStorage, discoverModels } from "./pi-model-discovery.js";
 import { stripToolResultDetails } from "./session-transcript-repair.js";
 
@@ -283,7 +284,8 @@ export async function runBtwSideQuestion(
     await blockEmitChain;
   };
 
-  const stream = streamSimple(
+  const stream = await streamWithPayloadPatch(
+    streamSimple,
     model,
     {
       systemPrompt: buildBtwSystemPrompt(),
@@ -308,6 +310,13 @@ export async function runBtwSideQuestion(
       reasoning: undefined,
       signal: params.opts?.abortSignal,
     },
+    (payloadObj) => {
+      // BTW is intentionally tool-less. Some OpenAI-compatible providers reject
+      // the empty tools arrays injected for generic tool-history replay.
+      if (Array.isArray(payloadObj.tools) && payloadObj.tools.length === 0) {
+        delete payloadObj.tools;
+      }
+    },
   );
 
   let finalEvent: