fix(thinking-block-validator): reuse signed thinking parts

Preserve prior signed Anthropic thinking blocks instead of creating unsigned synthetic placeholders, and skip injection when no signed block exists. Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent) Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
2026-03-24 17:22:07 +09:00
parent 500784a9b9
commit 0732cb85f9
2 changed files with 136 additions and 47 deletions
@@ -0,0 +1,108 @@
+const { describe, expect, test } = require("bun:test")
+
+const { createThinkingBlockValidatorHook } = require("./hook")
+
+type TestPart = {
+  type: string
+  id: string
+  text?: string
+  thinking?: string
+  data?: string
+  signature?: string
+}
+
+type TestMessage = {
+  info: {
+    role: string
+    id?: string
+    modelID?: string
+  }
+  parts: TestPart[]
+}
+
+function createMessage(info: TestMessage["info"], parts: TestPart[]): TestMessage {
+  return { info, parts }
+}
+
+function createTextPart(id: string, text: string): TestPart {
+  return { type: "text", id, text }
+}
+
+function createSignedThinkingPart(id: string, thinking: string, signature: string): TestPart {
+  return { type: "thinking", id, thinking, signature }
+}
+
+function createRedactedThinkingPart(id: string, signature: string): TestPart {
+  return { type: "redacted_thinking", id, data: "encrypted", signature }
+}
+
+describe("createThinkingBlockValidatorHook", () => {
+  test("reuses the previous signed thinking part verbatim when assistant content lacks a leading thinking block", async () => {
+    const transform = Reflect.get(createThinkingBlockValidatorHook(), "experimental.chat.messages.transform")
+    expect(typeof transform).toBe("function")
+
+    const previousThinkingPart = createSignedThinkingPart("prt_prev_signed", "prior reasoning", "sig_prev")
+    const targetTextPart = createTextPart("prt_target_text", "tool result")
+    const messages: TestMessage[] = [
+      createMessage({ role: "user", modelID: "claude-opus-4-6-thinking" }, [createTextPart("prt_user_text", "continue")]),
+      createMessage({ role: "assistant", id: "msg_prev" }, [previousThinkingPart, createTextPart("prt_prev_text", "done")]),
+      createMessage({ role: "assistant", id: "msg_target" }, [targetTextPart]),
+    ]
+
+    await Reflect.apply(transform, undefined, [{}, { messages }])
+
+    expect(messages[2]?.parts[0]).toBe(previousThinkingPart)
+    expect(messages[2]?.parts).toEqual([previousThinkingPart, targetTextPart])
+  })
+
+  test("skips injection when no signed Anthropic thinking part exists in history", async () => {
+    const transform = Reflect.get(createThinkingBlockValidatorHook(), "experimental.chat.messages.transform")
+    expect(typeof transform).toBe("function")
+
+    const targetTextPart = createTextPart("prt_target_text", "tool result")
+    const messages: TestMessage[] = [
+      createMessage({ role: "user", modelID: "claude-opus-4-6-thinking" }, [createTextPart("prt_user_text", "continue")]),
+      createMessage({ role: "assistant", id: "msg_prev" }, [{ type: "reasoning", id: "prt_reason", text: "gpt reasoning" }]),
+      createMessage({ role: "assistant", id: "msg_target" }, [targetTextPart]),
+    ]
+
+    await Reflect.apply(transform, undefined, [{}, { messages }])
+
+    expect(messages[2]?.parts).toEqual([targetTextPart])
+  })
+
+  test("does not inject when the assistant message already starts with redacted thinking", async () => {
+    const transform = Reflect.get(createThinkingBlockValidatorHook(), "experimental.chat.messages.transform")
+    expect(typeof transform).toBe("function")
+
+    const existingThinkingPart = createRedactedThinkingPart("prt_redacted", "sig_redacted")
+    const targetTextPart = createTextPart("prt_target_text", "tool result")
+    const messages: TestMessage[] = [
+      createMessage({ role: "user", modelID: "claude-opus-4-6-thinking" }, [createTextPart("prt_user_text", "continue")]),
+      createMessage({ role: "assistant", id: "msg_target" }, [existingThinkingPart, targetTextPart]),
+    ]
+
+    await Reflect.apply(transform, undefined, [{}, { messages }])
+
+    expect(messages[1]?.parts).toEqual([existingThinkingPart, targetTextPart])
+  })
+
+  test("skips processing for models without extended thinking", async () => {
+    const transform = Reflect.get(createThinkingBlockValidatorHook(), "experimental.chat.messages.transform")
+    expect(typeof transform).toBe("function")
+
+    const previousThinkingPart = createSignedThinkingPart("prt_prev_signed", "prior reasoning", "sig_prev")
+    const targetTextPart = createTextPart("prt_target_text", "tool result")
+    const messages: TestMessage[] = [
+      createMessage({ role: "user", modelID: "gpt-5.4" }, [createTextPart("prt_user_text", "continue")]),
+      createMessage({ role: "assistant", id: "msg_prev" }, [previousThinkingPart]),
+      createMessage({ role: "assistant", id: "msg_target" }, [targetTextPart]),
+    ]
+
+    await Reflect.apply(transform, undefined, [{}, { messages }])
+
+    expect(messages[2]?.parts).toEqual([targetTextPart])
+  })
+})
+
+export {}