fix: preserve non-terminal subagent tool-use turns

src/wrapper/cli.mjs

@@ -10,6 +10,10 @@ async function sleep(ms) {
   await new Promise((resolve) => setTimeout(resolve, ms));
 }
 
+function isTerminalAssistantStopReason(stopReason) {
+  return stopReason === "stop" || stopReason === "length" || stopReason === "aborted" || stopReason === "error";
+}
+
 async function appendJsonLine(path, value) {
   await appendBestEffort(path, `${JSON.stringify(value)}\n`);
 }
@@ -41,6 +45,7 @@ function makeResult(meta, startedAt, input = {}) {
     finishedAt: new Date().toISOString(),
     exitCode,
     stopReason: input.stopReason ?? (exitCode === 0 ? undefined : "error"),
+    rawStopReason: input.rawStopReason,
     finalText: input.finalText ?? "",
     usage: input.usage,
     stdoutPath: meta.stdoutPath,
@@ -71,6 +76,7 @@ async function runWrapper(meta, startedAt) {
   let finalText = "";
   let resolvedModel = meta.resolvedModel;
   let stopReason;
+  let rawStopReason;
   let usage = undefined;
   let stdoutBuffer = "";
   let stderrText = "";
@@ -122,9 +128,10 @@ async function runWrapper(meta, startedAt) {
       finalText = normalized.text;
       resolvedModel = normalized.model ?? resolvedModel;
       stopReason = normalized.stopReason ?? stopReason;
+      rawStopReason = normalized.rawStopReason ?? rawStopReason;
       usage = normalized.usage ?? usage;
 
-      if (normalized.stopReason) {
+      if (isTerminalAssistantStopReason(normalized.stopReason)) {
         void forceChildExitAfterSemanticCompletion();
       }
     }
@@ -208,6 +215,7 @@ async function runWrapper(meta, startedAt) {
   return makeResult(meta, startedAt, {
     exitCode,
     stopReason,
+    rawStopReason,
     finalText,
     usage,
     resolvedModel,

src/wrapper/cli.test.ts

@@ -191,6 +191,72 @@ test("wrapper exits and writes result.json when the pi child cannot be spawned",
   assert.match(result.errorMessage ?? "", /ENOENT|not found|spawn pi/i);
 });
 
+test("wrapper does not exit early on non-terminal toolUse assistant messages", async () => {
+  const dir = await mkdtemp(join(tmpdir(), "pi-subagents-wrapper-"));
+  const metaPath = join(dir, "meta.json");
+  const resultPath = join(dir, "result.json");
+  const eventsPath = join(dir, "events.jsonl");
+  const piPath = join(dir, "pi");
+
+  await writeFile(
+    piPath,
+    [
+      `#!${process.execPath}`,
+      "console.log(JSON.stringify({type:'message_end',message:{role:'assistant',content:[{type:'text',text:'starting'}],model:'openai/gpt-5',stopReason:'toolUse'}}));",
+      "setTimeout(() => console.log(JSON.stringify({type:'tool_execution_start',toolName:'read',args:{path:'src/auth.ts'}})), 400);",
+      "setTimeout(() => console.log(JSON.stringify({type:'message_end',message:{role:'assistant',content:[{type:'text',text:'final'}],model:'openai/gpt-5',stopReason:'stop'}})), 700);",
+      "setTimeout(() => process.exit(0), 1200);",
+    ].join("\n"),
+    "utf8",
+  );
+  await chmod(piPath, 0o755);
+
+  await writeFile(
+    metaPath,
+    JSON.stringify(
+      {
+        runId: "run-1",
+        mode: "single",
+        agent: "scout",
+        agentSource: "builtin",
+        task: "inspect auth",
+        cwd: dir,
+        requestedModel: "openai/gpt-5",
+        resolvedModel: "openai/gpt-5",
+        startedAt: "2026-04-09T00:00:00.000Z",
+        sessionPath: join(dir, "child-session.jsonl"),
+        eventsPath,
+        resultPath,
+        stdoutPath: join(dir, "stdout.log"),
+        stderrPath: join(dir, "stderr.log"),
+        transcriptPath: join(dir, "transcript.log"),
+        systemPromptPath: join(dir, "system-prompt.md"),
+      },
+      null,
+      2,
+    ),
+    "utf8",
+  );
+
+  const wrapperPath = join(dirname(fileURLToPath(import.meta.url)), "cli.mjs");
+  const child = spawn(process.execPath, [wrapperPath, metaPath], {
+    env: { ...process.env, PATH: dir },
+    stdio: ["ignore", "pipe", "pipe"],
+  });
+
+  const exitCode = await waitForExit(child, 2500);
+  assert.equal(exitCode, 0);
+
+  const result = JSON.parse(await readFile(resultPath, "utf8"));
+  assert.equal(result.exitCode, 0);
+  assert.equal(result.stopReason, "stop");
+  assert.equal(result.rawStopReason, "stop");
+  assert.equal(result.finalText, "final");
+
+  const eventsText = await readFile(eventsPath, "utf8");
+  assert.match(eventsText, /"type":"tool_call"/);
+});
+
 test("wrapper exits and writes result.json after terminal output even if the pi child lingers", async () => {
   const dir = await mkdtemp(join(tmpdir(), "pi-subagents-wrapper-"));
   const metaPath = join(dir, "meta.json");