Bug: Incompatibility with Anthropic API due to input_schema structure

[RMStankiewicz]

Client Information

• LLM Client: Anthropic Claude Code
• Client Config: Standard configuration in the .claude.json project file.
• Using MCP Remote?: No (the server is run locally via stdio)
• MCP Server: @cloudflare/mcp-server-cloudflare
• Prompt: N/A (the error occurs on application startup during tool registration)

Describe the bug
When using the @cloudflare/mcp-server-cloudflare with Anthropic's Claude Code, the server fails to load correctly due to an API validation error from the Anthropic backend.

The error log indicates that the input_schema for one of the tools uses an unsupported structure (oneOf, allOf, or anyOf) at the top level, which causes the API to reject the tool definition.

Error Log:

API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"tools.78.custom.input_schema: input_schema does not support oneOf, allOf, or anyOf at the top level"},"request_id":"req_011CSmBV2omZKeFAsJytXZWK"}

[Maximo-Guk]

Hey @RMStankiewicz , I would recommend using the Cloudflare Developer Platform connector, which you can find in your Claude Desktop app under settings -> connectors -> browse connectors

You can add other Cloudflare MCP servers by adding them via the custom connector flow and adding their server url, which you can find in the README here.

The @cloudflare/mcp-server-cloudflare npm package hasn't been updated in a while, and only supports stdio transport.