ClaudeCode 报 400（thinking block）的解决方案

最近在用 cc 写东西的时候遇到过几次 400 的错误，具体表现为

API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.7.content.0: Invalid `signature` in `thinking`block"},"request_id":"req_xxxxxxx"}

解决步骤：
1、退出 Claude Code
2、找到对话文件：

# linux or mac ls -la ~/.claude/projects/
# win dir %USERPROFILE%\.claude\projects\
# 在项目文件夹中查找最大/最新的 .jsonl 文件 

备份并修复文件：

import json

filepath = "/path/to/your/session.jsonl"

with open(filepath, 'r') as f:
  lines = f.readlines()

with open(filepath, 'w') as f:
  for line in lines:
    if not line.strip():
      continue data = json.loads(line)
    if 'message' in data and 'content' in data['message']:
      if isinstance(data['message']['content'], list):
        data['message']['content'] = [
          c for c in data['message']['content'] 
          if c.get('type') not in ('thinking', 'redacted_thinking')
        ]
    f.write(json.dumps(data) + '\n')

3、重启 ClaudeCode，/resume 恢复之前的记录，可以正常继续对话了

来源：[BUG] API Error 400 - Thinking Block Modification Error · Issue #10199 · anthropics/claude-code · GitHub