From d4375300cde71320cdd2a012304603efe9eb5cf9 Mon Sep 17 00:00:00 2001
From: weichen <weichen@home.local>
Date: Thu, 1 Oct 2026 06:03:19 +0000
Subject: [PATCH] Add thinking duration to message parts

Why: The chat timeline needs a persisted thinking duration, and tool duration already lives on the tool call, so the thinking part had nowhere to put it.
Evidence: go test ./... passes; the message golden now includes durationMs on the thinking part.
Impact: Additive JSON field with omitempty. Existing clients ignore unknown fields.
Refs: feature/chat-timeline-preview
Co-authored-by: Cursor <cursoragent@cursor.com>
---
 conformance_test.go          | 2 +-
 model.go                     | 4 ++++
 testdata/golden/message.json | 3 ++-
 ts/types.ts                  | 1 +
 4 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/conformance_test.go b/conformance_test.go
index b8082f1..5e65262 100644
--- a/conformance_test.go
+++ b/conformance_test.go
@@ -42,7 +42,7 @@ func sampleMessage() Message {
 		ID: "msg_abc123def456", ConversationID: "cnv_abc123def456", RunID: "run_abc123def456",
 		Role: RoleAssistant,
 		Parts: []Part{
-			{Type: PartThinking, Text: "考虑先检索…", Process: true},
+			{Type: PartThinking, Text: "考虑先检索…", Process: true, DurationMs: 1500},
 			{Type: PartToolCall, Process: true, ToolCall: &ToolCallPart{ID: "call_1", Name: "history_search", Arguments: `{"q":"部署"}`, Duration: 12.5}},
 			{Type: PartToolResult, Process: true, ToolResult: &ToolResultPart{CallID: "call_1", Status: "ok", Summary: "3 条命中"}},
 			{Type: PartText, Text: "根据历史记录……"},
diff --git a/model.go b/model.go
index ddb4128..dbf0365 100644
--- a/model.go
+++ b/model.go
@@ -89,6 +89,10 @@ type Part struct {
 
 	// 过程标记：true 的部件在 run 终态后由前端折叠为摘要行（4.2）。
 	Process bool `json:"process,omitempty"`
+
+	// DurationMs 是 thinking 部件的思考时长（毫秒，从首个推理增量到最后一个）。
+	// 工具耗时在 ToolCallPart.Duration，不复用本字段。
+	DurationMs float64 `json:"durationMs,omitempty"`
 }
 
 type ToolCallPart struct {
diff --git a/testdata/golden/message.json b/testdata/golden/message.json
index a774ab6..11ece24 100644
--- a/testdata/golden/message.json
+++ b/testdata/golden/message.json
@@ -7,7 +7,8 @@
     {
       "type": "thinking",
       "text": "考虑先检索…",
-      "process": true
+      "process": true,
+      "durationMs": 1500
     },
     {
       "type": "tool_call",
diff --git a/ts/types.ts b/ts/types.ts
index bd6b748..e127d6a 100644
--- a/ts/types.ts
+++ b/ts/types.ts
@@ -35,6 +35,7 @@ export interface Part {
   card?: { kind: string; data: UINode[]; cardId?: ID }; // cardId 非空 = 收件箱卡片引用部件（submit_card）
   error?: { code: string; message: string };
   process?: boolean; // run 终态后折叠为摘要行
+  durationMs?: number; // thinking 部件的思考时长（毫秒）；工具耗时在 toolCall.durationMs
 }
 
 export interface Message {