[Bug] Malformed MCP Tool Schema Causes Persistent Anthropic API Errors in Subsequent Requests

Bug Description
bad tool schema from MCP can mess up claude. it's "infectious". subsequent conversation calls about other subject return same error.

Environment Info

• Platform: darwin
• Terminal: ghostty
• Version: 2.1.140
• Feedback ID: 97389ded-ec31-4412-b337-8823d299ac11

Errors

[{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/roger/.local/share/claude/versions/2.1.140 (expected in multi-process scenarios)\n    at g16 (/$bunfs/root/src/entrypoints/cli.js:2672:2257)\n    at RLH (/$bunfs/root/src/entrypoints/cli.js:2672:1337)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-13T22:08:00.981Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"tools.14.custom.input_schema: input_schema does not support oneOf, allOf, or anyOf at the top level\"},\"request_id\":\"req_011Cb1LAXQoCPNZTSis6j8vz\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:11:59486)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:51:7694)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-13T22:08:53.746Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"tools.14.custom.input_schema: input_schema does not support oneOf, allOf, or anyOf at the top level\"},\"request_id\":\"req_011Cb1LBHLzKAS8p4KDDWVpH\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:11:59486)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:51:7694)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-13T22:09:04.094Z"}]