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

Bug Description
API Error: 400
{"type":"error","error":{"type":"invalid_request_error","message":"messages.11.content.1:
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_011CYEsdjv8Qey8yhaMjPS4C"}

Environment Info

• Platform: darwin
• Terminal: windsurf
• Version: 2.1.44 (do not say update to .45 -- that is nerf'ed beyond usability)
• Feedback ID: 6899a5c7-9440-4d7f-abb6-619fb33c05d6

Errors

[{"error":"Error: Tool mcp__Neon__run_sql not found\n    at z94 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:2180:11981)\n    at dK (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:20892)\n    at U2 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:39409)\n    at El (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:50096)\n    at AQ (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:86682)\n    at Y61 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:85651)\n    at xl (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:85473)\n    at Cl (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:81862)\n    at h6 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:6447)\n    at m1 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:4939)","timestamp":"2026-02-18T04:05:46.058Z"},{"error":"Error: Tool mcp__Neon__list_projects not found\n    at z94 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:2180:11981)\n    at dK (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:20892)\n    at U2 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:39409)\n    at El (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:50096)\n    at AQ (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:86682)\n    at Y61 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:85651)\n    at xl (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:85473)\n    at Cl (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:81862)\n    at h6 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:6447)\n    at m1 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:4939)","timestamp":"2026-02-18T04:05:46.059Z"},{"error":"Error: Tool mcp__Neon__run_sql not found\n    at z94 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:2180:11981)\n    at dK (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:20892)\n    at U2 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:39409)\n    at El (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:50096)\n    at AQ (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:86682)\n    at Y61 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:85651)\n    at xl (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:85473)\n    at Cl (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:81862)\n    at h6 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:6447)\n    at m1 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:4939)","timestamp":"2026-02-18T04:05:46.059Z"},{"error":"Error: Tool mcp__Neon__get_database_tables not found\n    at z94 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:2180:11981)\n    at dK (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:20892)\n    at U2 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:39409)\n    at El (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:50096)\n    at AQ (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:86682)\n    at Y61 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:85651)\n    at xl (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:85473)\n    at Cl (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:81862)\n    at h6 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:6447)\n    at m1 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:717:4939)","timestamp":"2026-02-18T04:05:46.059Z"},{"error":"Error: Tool mcp__Neon__run_sql not found\n    at z94 (file:///usr/local/lib/node_modules/@anthropic-ai/claude-code/cli.js:2180:11981)\n    a…

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