[Bug] Anthropic API Error: Invalid Tool Property Name Format

Bug Description
Claude does not want to continue due to API Error. Nothing is possible anymore.
● API Error: 400 tools.14.custom.input_schema.properties: Property keys should match
pattern '^[a-zA-Z0-9_.-]{1,64}$'

Environment Info

• Platform: linux
• Terminal: ghostty
• Version: 2.1.215
• Feedback ID: 51e0c00b-3ff3-43a4-93c2-05224c698ec5

Errors

[{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"tools.14.custom.input_schema.properties: Property keys should match pattern '^[a-zA-Z0-9_.-]{1,64}$'\"},\"request_id\":\"req_011CdDLjKQe2LJzoQzyy8Y5t\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:40:48734)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:80:7690)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-07-20T12:52:21.962Z"}]