[Bug] Anthropic API Error: Cannot modify thinking blocks in assistant message

Resolved 💬 3 comments Opened Dec 8, 2025 by leaf76 Closed Dec 9, 2025

Bug Description
⏺ Bash(git diff --name-only 2>&1)
⎿  scripts/build_js.ts
src/controllers/admin_router.py
src/controllers/analytics_router.py
… +4 lines (ctrl+o to expand)

⏺ Bash(git diff src/controllers/auth_router.py | grep -A3 -B3 "1513\|_base_context" 2>&1 | head -20)
⎿  (No content)
⎿  Context low · Run /compact to compact & continue

/compact

⎿ Error: Error during compaction: Error: API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.1.content.14: thinking or redacted_thinking blocks in the latest assistant message cannot be
modified. These blocks must remain as they were in the original response."},"request_id":"req_011CVuC41MpFHWGxV8e4ZE8o"}

continue

⎿  Context low · Run /compact to compact & continue

Environment Info

  • Platform: darwin
  • Terminal: Apple_Terminal
  • Version: 2.0.61
  • Feedback ID: cfcb83a9-c51b-4d0c-9e33-581c96bcfb6a

Errors

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