diff --git a/_AI_USAGE_LOG.md b/_AI_USAGE_LOG.md
index 78aa5f5..ebdfad4 100644
--- a/_AI_USAGE_LOG.md
+++ b/_AI_USAGE_LOG.md
@@ -51,4 +51,5 @@
 
 (End of file - total 50 lines)
 | 2026-08-09 10:50 | 反馈迭代 | 里程碑3.1 backlog 清理（retro 3 项）：① chat_structured 增加 token 超限检测（渲染后估算超限→truncate_cb→重渲染，与 chat 流程一致）TDD RED→GREEN 新增 test_chat_structured_truncation_callback_triggered；② 清理 test_inference_engine.py 未用导入（pytest/json/ChatMessage）；③ HttpLLMClient 增加上下文管理器（__enter__/__exit__ 退出时关闭底层 httpx.Client 释放连接）TDD 新增 test_client_context_manager_closes_transport；pytest 全量 119 passed 覆盖 100.00%，fail_under=99 达标；提交见 git log | src/genesis/inference/engine.py, src/genesis/inference/client.py, tests/test_inference_engine.py, tests/test_inference_client.py, _AI_USAGE_LOG.md | deepseek-v4-flash-free |
-| 2026-08-09 11:20 | 反馈迭代 | Web UI 设计评审（v1.0→v1.1，7 项发现全修）：以大赛手册+api-design 为权威基准审查 web-ui-design.md——F1 上传区补「概要设计做成说明书」独立 write_instruction file_type（api-design §2.2 连带扩展）+ 命名统一；F2 §4.1 任务队列 Redis 写死→抽象 TaskQueue（InMemory 默认/Redis/Valkey 可选）；F3 新增设置页 §3.6；F4 预览路径改 ContentBlock→chapter_html+docx；F5 生成页新增规则冲突浮动卡片（WS conflict_pending→conflicts/{id}/resolve）；F6 新增会话历史页 §3.7；F7 新增 §7 无障碍与设计规范。同步 design.md §8 简版镜像（上传区/预览/队列/导航历史/冲突卡片/设置历史简版//history 命令）；产出评审报告 docs/web-ui-design-review-v1.1.md；docs/design.md、docs/api-design.md 连带修订 | docs/web-ui-design.md, docs/web-ui-design-review-v1.1.md, docs/api-design.md, docs/design.md, _AI_USAGE_LOG.md | deepseek-v4-flash-free |
+| 2026-08-09 11:20 | 反馈迭代 | Web UI 设计评审（v1.0→v1.1，7 项发现全修）：以大赛手册+api-design 为权威基准审查 web-ui-design.md——F1 上传区补「概要设计做成说明书」独立 write_instruction file_type（api-design §2.2 连带扩展）+ 命名统一；F2 §4.1 任务队列 Redis 写死→抽象 TaskQueue（InMemory 默认/Redis/Valkey 可选）；F3 新增设置页 §3.6；F4 预览路径改 ContentBlock→chapter_html+docx；F5 生成页新增规则冲突卡片（WS conflict_pending→conflicts/{id}/resolve）；F6 新增会话历史页 §3.7；F7 新增 §7 无障碍与设计规范。同步 design.md §8 镜像（上传区/设置/队列/会话/冲突卡片/历史简版//history 命令）；产出评审报告 docs/web-ui-design-review-v1.1.md；docs/design.md、docs/api-design.md 连带修订 | docs/web-ui-design.md, docs/web-ui-design-review-v1.1.md, docs/api-design.md, docs/design.md, _AI_USAGE_LOG.md | deepseek-v4-flash-free |
+| 2026-08-09 11:45 | Agent 实现 | LLM 错误码对齐 Task1：异常树 error_code 类属性（LLMError 基类 None + four 子类 four 码，对齐 api-design §7），沿用现有中文 docstring 未改动。TDD RED（AttributeError: type object 'LLMError' has no attribute 'error_code'）→ GREEN（聚焦 4 passed，exceptions.py 100%）；聚焦单文件运行触发全库 fail-under=99 coverage exit 1 为基线行为（总覆盖 9.95%），与本次改动无关；加入 _AI_USAGE_LOG.md 提交 | src/genesis/inference/exceptions.py, tests/test_inference_errors.py, _AI_USAGE_LOG.md | deepseek-v4-flash-free |
diff --git a/src/genesis/inference/exceptions.py b/src/genesis/inference/exceptions.py
index 8fed13d..4aca4c6 100644
--- a/src/genesis/inference/exceptions.py
+++ b/src/genesis/inference/exceptions.py
@@ -3,19 +3,24 @@ from __future__ import annotations
 
 class LLMError(Exception):
     """LLM 调用相关的异常基类（api-design §7 映射基底）"""
+    error_code: str | None = None   # api §7 错误码（机器可读）；新增子类必须覆写
 
 
 class LLMNetworkError(LLMError):
     """网络失败 / 5xx 重试耗尽（可重试语义）"""
+    error_code = "LLM_NETWORK_ERROR"
 
 
 class LLMTimeoutError(LLMError):
     """LLM 调用超时（api-error: LLM_TIMEOUT 502）"""
+    error_code = "LLM_TIMEOUT"
 
 
 class LLMNotConfiguredError(LLMError):
     """Key / 模型缺失（api-error: LLM_NOT_CONFIGURED 503）"""
+    error_code = "LLM_NOT_CONFIGURED"
 
 
 class LLMResponseError(LLMError):
-    """响应结构损坏（JSON 解析失败等）"""
\ No newline at end of file
+    """响应结构损坏（JSON 解析失败等）"""
+    error_code = "LLM_PARSE_ERROR"
\ No newline at end of file
diff --git a/tests/test_inference_errors.py b/tests/test_inference_errors.py
index 7020f70..ea409bc 100644
--- a/tests/test_inference_errors.py
+++ b/tests/test_inference_errors.py
@@ -18,4 +18,18 @@ def test_error_hierarchy():
 
 def test_error_message_roundtrip():
     e = LLMTimeoutError("timeout!")
-    assert str(e) == "timeout!"
\ No newline at end of file
+    assert str(e) == "timeout!"
+
+
+def test_error_code_class_attributes():
+    # error_code 与 api-design §7 错误码表一一对应（机器可读事实源）
+    assert LLMError.error_code is None
+    assert LLMTimeoutError.error_code == "LLM_TIMEOUT"
+    assert LLMNetworkError.error_code == "LLM_NETWORK_ERROR"
+    assert LLMNotConfiguredError.error_code == "LLM_NOT_CONFIGURED"
+    assert LLMResponseError.error_code == "LLM_PARSE_ERROR"
+
+
+def test_error_code_inherited_by_instance():
+    e = LLMNetworkError("network")
+    assert e.error_code == "LLM_NETWORK_ERROR"
\ No newline at end of file