guided: the stub accepts the engine's merged first message; compile trigger -5

.github/workflows/cowork-guided-packet-compile-fixture.yml

@@ -8,7 +8,7 @@ name: guided-packet-compile-fixture
 # The first steps refuse unless BUILDER_HEAD is an ancestor of the pushed commit and the whole diff is that one line.
 on:
   push:
-    branches: [cowork/guided-packet-compile-fixture-4]
+    branches: [cowork/guided-packet-compile-fixture-5]
 permissions:
   contents: read
 env:
@@ -22,7 +22,7 @@ env:
   DEPENDENCY_LIST_SHA256: f8255bc2b622416d260ff522134beca24b5c0c503700343012a6d2a7e29cdfbe
 jobs:
   compile-only:
-    if: github.repository == 'yanlingLabs/winter-runtime-sdk' && github.event_name == 'push' && github.ref == 'refs/heads/cowork/guided-packet-compile-fixture-4' && github.event.created == true && github.run_attempt == '1'
+    if: github.repository == 'yanlingLabs/winter-runtime-sdk' && github.event_name == 'push' && github.ref == 'refs/heads/cowork/guided-packet-compile-fixture-5' && github.event.created == true && github.run_attempt == '1'
     runs-on: ubuntu-24.04-arm
     timeout-minutes: 30
     steps:

scripts/guest-guided-build/README.md

@@ -293,7 +293,7 @@ pruned-edge and tsconfig-`paths` rules, which the reader builder refuses. It is
 ## The run
 
 `.github/workflows/cowork-guided-packet-compile-fixture.yml` fires only on the **first creation** of the branch
-`cowork/guided-packet-compile-fixture-4` (`created == true`, `run_attempt == '1'`). It has no pull request,
+`cowork/guided-packet-compile-fixture-5` (`created == true`, `run_attempt == '1'`). It has no pull request,
 dispatch, schedule or tag trigger, no `paths` filter, no secrets, `contents: read`, no sudo, and it runs on
 `ubuntu-24.04-arm`. It curls the pinned Bun zip and the 20 pinned tarballs (each checked by a strict checksum),
 runs `build.py` (which runs `bun build --compile` four times, `cc` six times, plus the semantic parser runs) and

scripts/guest-guided-build/guided-compile-inputs.pin.json

@@ -234,7 +234,7 @@
   ]
  },
  "trigger": {
-  "branch": "cowork/guided-packet-compile-fixture-4",
+  "branch": "cowork/guided-packet-compile-fixture-5",
   "workflow": "cowork-guided-packet-compile-fixture.yml",
   "sourceWorkflow": "cowork-guided-build-source.yml"
  },

scripts/guest-guided-build/test_guided_build.py

@@ -427,7 +427,7 @@ def test_retention_is_capped_at_seven_days_and_the_limit_is_stated(self):
         self.assertEqual(pins.MAX_PACKET_BYTES,1024**3)
     def test_trigger_branch_is_new_and_not_a_reader_or_hosted_name(self):
         for used in ('cowork/instruction-reader-compile-fixture','cowork/reader-hosted-dependency-probe','cowork/reader-hosted-fixture-stderr','cowork/guided-packet-build'):self.assertNotEqual(pins.TRIGGER_BRANCH,used)
-        self.assertEqual(pins.TRIGGER_BRANCH,'cowork/guided-packet-compile-fixture-4')
+        self.assertEqual(pins.TRIGGER_BRANCH,'cowork/guided-packet-compile-fixture-5')
 
 class NoExecutionTests(unittest.TestCase):
     SOURCES=('build.py','graph.py','acquire.py','pins.py')

scripts/guest-guided-provider/real-request-layout.fixture.json

@@ -0,0 +1,52 @@
+{
+ "source": {
+  "note": "buildRequestMessages output (renderUserContext with one claudeMd entry, then the prompt), generated from the pinned agent-sdk source; regenerate only when the pin moves",
+  "repository": "yanlingLabs/winter-agent-sdk",
+  "commit": "9c980c326638489e0183d7fcddcf1a93553be0ba",
+  "path": "packages/runtime/src/context/request-layout.ts",
+  "sha256": "8a664c059c43016f188f34bde83ad1fb3681025e10fb9d86f4541fa36d4fd605"
+ },
+ "dispatch1": [
+  {
+   "role": "user",
+   "content": [
+    {
+     "type": "text",
+     "text": "<system-reminder>\nAs you answer the user's questions, you can use the following context:\n# claudeMd\nGuided hosted run guidance, first version.\nThe shared guidance marker is ALPHA.\n\n\n      IMPORTANT: this context may or may not be relevant to your tasks. You should not respond to this context unless it is highly relevant to your task.\n</system-reminder>\n\n"
+    },
+    {
+     "type": "text",
+     "text": "Answer with the first scripted reply."
+    }
+   ]
+  }
+ ],
+ "dispatch2": [
+  {
+   "role": "user",
+   "content": [
+    {
+     "type": "text",
+     "text": "<system-reminder>\nAs you answer the user's questions, you can use the following context:\n# claudeMd\nGuided hosted run guidance, second version.\nThe shared guidance marker is BRAVO.\n\n\n      IMPORTANT: this context may or may not be relevant to your tasks. You should not respond to this context unless it is highly relevant to your task.\n</system-reminder>\n\n"
+    },
+    {
+     "type": "text",
+     "text": "Answer with the first scripted reply."
+    }
+   ]
+  },
+  {
+   "role": "assistant",
+   "content": [
+    {
+     "type": "text",
+     "text": "first deterministic answer"
+    }
+   ]
+  },
+  {
+   "role": "user",
+   "content": "Answer with the second scripted reply."
+  }
+ ]
+}

scripts/guest-guided-provider/stub.test.ts

@@ -1,3 +1,4 @@
+import { readFileSync } from "node:fs";
 import { expect, test } from "bun:test";
 import { createGuidedFixturePort, encodeFrame, LIMITS, SELECTION, STANDIN_SELECTION, sha256 } from "./stub.ts";
 
@@ -223,3 +224,71 @@ test("the selection argument is explicit and exact: undefined is the default; a
   expect(() => createGuidedFixturePort(bytes, hash, SELECTION)).not.toThrow();
   for (const bad of [{ ...SELECTION }, { ...STANDIN_SELECTION }, null, "winter-standin", {}, 0] as any[]) expect(() => createGuidedFixturePort(bytes, hash, bad)).toThrow("fixture refused");
 });
+
+// The engine merges the meta userContext message into the following user turn (request-layout.ts buildRequestMessages), so a real first message has no `isMeta`.
+const merged = (second = false) => ({ ...turn(second), messages: [{ role: "user", content: [{ type: "text", text: `<system-reminder>\n# claudeMd\nSHARED:${second ? "new" : "old"}\nSOURCE:root\nSOURCE:cwd\n\n</system-reminder>\n` }, { type: "text", text: "question" }] }] });
+const withTurn = (value: unknown, ordinal = 1, id = "invocation-one") => ({ ...request("begin", 0, ordinal, id), turn: value });
+const refusedAt = async (value: unknown) => { const p = port(); try { await p.exchange(encodeFrame(withTurn(value))); } catch (error: any) { return error.site; } return undefined; };
+
+test("the real merged first message (a reminder block then the prompt, no isMeta) is the current userContext, and the old separate-meta shape still is", async () => {
+  const p = port();
+  expect(decode(await p.exchange(encodeFrame(withTurn(merged()))))).toMatchObject({ kind: "accepted" });
+  await finish(port());
+  const q = port();
+  expect(decode(await q.exchange(encodeFrame(withTurn(turn()))))).toMatchObject({ kind: "accepted" });
+});
+test("a first message that is neither meta nor opens with the reminder marker is not the userContext", async () => {
+  const plain = { ...turn(), messages: [{ role: "user", content: [{ type: "text", text: "SHARED:old\nSOURCE:root\nSOURCE:cwd" }, { type: "text", text: "question" }] }] };
+  expect(await refusedAt(plain)).toBe("not_meta");
+  const late = { ...turn(), messages: [{ role: "user", content: [{ type: "text", text: "question" }, { type: "text", text: "<system-reminder>\nSHARED:old\nSOURCE:root\nSOURCE:cwd\n</system-reminder>" }] }] };
+  expect(await refusedAt(late)).toBe("not_meta");
+  const text = { ...turn(), messages: [{ role: "user", content: "SHARED:old\nSOURCE:root\nSOURCE:cwd" }] };
+  expect(await refusedAt(text)).toBe("not_meta");
+  expect(await refusedAt({ ...turn(), messages: [{ role: "assistant", content: "<system-reminder>" }, { role: "user", content: "q" }] })).toBe("not_meta");
+  // the reminder-first shape needs an ARRAY of at least two blocks whose first is one closed reminder
+  expect(await refusedAt({ ...turn(), messages: [{ role: "user", content: "<system-reminder>\nSHARED:old\nSOURCE:root\nSOURCE:cwd\n</system-reminder>" }] })).toBe("not_meta");
+  expect(await refusedAt({ ...turn(), messages: [{ role: "user", content: [{ type: "text", text: "<system-reminder>\nSHARED:old\nSOURCE:root\nSOURCE:cwd\n</system-reminder>" }] }] })).toBe("not_meta");
+  expect(await refusedAt({ ...turn(), messages: [{ role: "user", content: [{ type: "text", text: "<system-reminder>\nSHARED:old\nSOURCE:root\nSOURCE:cwd" }, { type: "text", text: "q" }] }] })).toBe("not_meta");
+  expect(await refusedAt({ ...turn(), messages: [{ role: "user", content: [{ type: "text", text: "<system-reminder>\nSHARED:old\n</system-reminder>\nSOURCE:root\nSOURCE:cwd\n</system-reminder>" }, { type: "text", text: "q" }] }] })).toBe("not_meta");
+});
+test("reviewer probes: markers carried by the prompt block, or by one block the user typed, are not the userContext", async () => {
+  // (a) a reminder block with no markers, then a prompt block that carries them
+  const a = { ...turn(), messages: [{ role: "user", content: [{ type: "text", text: "<system-reminder>\nnothing here\n</system-reminder>\n" }, { type: "text", text: "SHARED:old\nSOURCE:root\nSOURCE:cwd" }] }] };
+  expect(await refusedAt(a)).toBe("user_marker");
+  // (b) one user-typed block that opens with the tag and carries the markers (no second block, no closing tag)
+  const b = { ...turn(), messages: [{ role: "user", content: [{ type: "text", text: "<system-reminder> SHARED:old\nSOURCE:root\nSOURCE:cwd" }] }] };
+  expect(await refusedAt(b)).toBe("not_meta");
+  expect(await refusedAt({ ...turn(), messages: [{ role: "user", content: "<system-reminder> SHARED:old\nSOURCE:root\nSOURCE:cwd" }] })).toBe("not_meta");
+  // an absent marker that only the prompt block carries is not the userContext's, so it does not refuse a good reminder
+  const c = merged(); (c.messages[0]!.content as any[])[1].text = "SHARED:new";
+  const p = port(); expect(decode(await p.exchange(encodeFrame(withTurn(c))))).toMatchObject({ kind: "accepted" });
+});
+test("the reminder marker does not excuse a missing or stale marker: user, system and absent checks still apply to the merged shape", async () => {
+  const stale = merged(); (stale.messages[0]!.content[0] as any).text = (stale.messages[0]!.content[0] as any).text.replace("SHARED:old", "SHARED:old\nSHARED:new");
+  expect(await refusedAt(stale)).toBe("absent_marker");
+  const missing = merged(); (missing.messages[0]!.content[0] as any).text = "<system-reminder>\nnothing\n</system-reminder>";
+  expect(await refusedAt(missing)).toBe("user_marker");
+  expect(await refusedAt({ ...merged(), system: "nothing", systemBlocks: undefined })).toBe("system_marker");
+});
+
+// The cross-check: the REAL engine layout, vendored with its source pinned, run through the stub for both dispatches of the hosted fixture.
+const layout = JSON.parse(readFileSync(new URL("./real-request-layout.fixture.json", import.meta.url), "utf8"));
+test("the vendored fixture names the pinned agent-sdk source it was generated from", () => {
+  expect(layout.source).toMatchObject({ repository: "yanlingLabs/winter-agent-sdk", commit: "9c980c326638489e0183d7fcddcf1a93553be0ba", path: "packages/runtime/src/context/request-layout.ts", sha256: "8a664c059c43016f188f34bde83ad1fb3681025e10fb9d86f4541fa36d4fd605" });
+  expect(layout.dispatch1[0].isMeta).toBeUndefined();
+  expect(layout.dispatch1).toHaveLength(1); expect(layout.dispatch1[0].content).toHaveLength(2);
+  expect(layout.dispatch2[0].isMeta).toBeUndefined(); expect(layout.dispatch2.map((m: any) => m.role)).toEqual(["user", "assistant", "user"]);
+});
+test("the stub accepts the real engine's request layout for both hosted dispatches, with the real guidance markers", async () => {
+  const markers = (version: string, mark: string) => [`Guided hosted run guidance, ${version} version.`, `The shared guidance marker is ${mark}.`];
+  const hosted = { version: 1, scope: { ...scope }, selection: SELECTION, steps: [
+    { system: ["Cowork current host context"], user: markers("first", "ALPHA"), absentSystem: [], absentUser: markers("second", "BRAVO"), response: "first deterministic answer" },
+    { system: ["Cowork current host context"], user: markers("second", "BRAVO"), absentSystem: [], absentUser: markers("first", "ALPHA"), response: "second deterministic answer" }] };
+  const p = port(hosted);
+  for (const [ordinal, key] of [[1, "dispatch1"], [2, "dispatch2"]] as const) {
+    const id = `invocation-${ordinal}`, t = { model: SELECTION.providerModelId, system: "Cowork current host context\n\nbase", messages: layout[key] };
+    expect(decode(await p.exchange(encodeFrame(withTurn(t, ordinal, id))))).toMatchObject({ kind: "accepted" });
+    for (const sequence of [1, 2]) await p.exchange(encodeFrame(request("next", sequence, ordinal, id)));
+  }
+  expect(p.receipt()).toMatchObject({ receivedBegins: 2, acceptedBegins: 2, completed: 2 });
+});

scripts/guest-guided-provider/stub.ts

@@ -60,6 +60,16 @@ function content(value: unknown): string {
   if (!Array.isArray(value)) refuse();
   return value.map(item => { const block = object(item); keys(block, ["type", "text"]); if (block.type !== "text" || typeof block.text !== "string") refuse(); return block.text; }).join("\n");
 }
+const REMINDER_OPEN = "<system-reminder>", REMINDER_CLOSE = "</system-reminder>";
+/** The merged layout's userContext: message content that is an array of at least two text blocks whose FIRST is one closed system-reminder
+ * (the prompt follows in its own block). Returns that first block's text, or undefined for any other content. */
+function reminderBlock(value: unknown): string | undefined {
+  if (!Array.isArray(value) || value.length < 2) return undefined;
+  const first = value[0] as ObjectValue | null;
+  if (!first || typeof first !== "object" || first.type !== "text" || typeof first.text !== "string") return undefined;
+  const body = first.text.trimEnd();
+  return first.text.startsWith(REMINDER_OPEN) && body.endsWith(REMINDER_CLOSE) && body.indexOf(REMINDER_CLOSE) === body.length - REMINDER_CLOSE.length ? first.text : undefined;
+}
 function optionalTurnFields(turn: ObjectValue): void {
   for (const key of ["cacheKey"]) if (turn[key] !== undefined) text(turn[key], LIMITS.requestBytes);
   if (turn.effort !== undefined && !(typeof turn.effort === "number" && Number.isFinite(turn.effort)) && !(typeof turn.effort === "string" && ["low", "medium", "high", "xhigh", "max"].includes(turn.effort))) refuse();
@@ -98,9 +108,16 @@ function validateTurn(value: unknown, step: Step, selection: StubSelection): Obj
   const current = object(turn.messages[0]);
   // Match current userContext only; stale markers in historical user/assistant text
   // cannot satisfy the next-dispatch guidance oracle.
-  if (current.role !== "user" || (selection !== STANDIN_SELECTION && current.isMeta !== true)) refuse("not_meta");
-  ordered(turn.system, step.system, "system_marker"); ordered(content(current.content), step.user, "user_marker");
-  absent(turn.system, step.absentSystem); absent(content(current.content), step.absentUser);
+  // The engine merges the meta userContext message into the user turn that follows it (request-layout.ts buildRequestMessages: consecutive
+  // user-role messages become one, which drops `isMeta`), so the real first message is `[closed <system-reminder> block, prompt block]` with no
+  // flag. The separate `isMeta` message is the other accepted shape. In the merged shape the markers are matched against the reminder block
+  // ONLY: a marker in the prompt block, or in a block the user typed, is not the userContext.
+  if (current.role !== "user") refuse("not_meta");
+  let userText: string;
+  if (selection === STANDIN_SELECTION || current.isMeta === true) userText = content(current.content);
+  else { const block = reminderBlock(current.content); if (block === undefined) return refuse("not_meta"); userText = block; }
+  ordered(turn.system, step.system, "system_marker"); ordered(userText, step.user, "user_marker");
+  absent(turn.system, step.absentSystem); absent(userText, step.absentUser);
   return frozen(turn);
 }
 export interface CapturedTurn { readonly invocationId: string; readonly ordinal: number; readonly sha256: string; readonly turn: Readonly<ObjectValue> }