Queries without input arguments create invalid tool definitions

[Willianvdv]

A query without arguments:

query TestQuery { me { id } }

Generates the following MCP tool response:

{"jsonrpc":"2.0","id":0,"result":{"protocolVersion":"2025-03-26","capabilities":{"tools":{"listChanged":true}},"serverInfo":{"name":"rmcp","version":"0.1.5"}}}

{"jsonrpc":"2.0","id":1,"result":{"tools":[{"name":"TestQuery","description":"The returned value is optional and has type `User`\n---\n\"\"\"Auser\"\"\"\ntype User implements Node {\n  id: ID!\n}\n","inputSchema":{"type":"object"},"annotations":{"readOnlyHint":true}}]}}

Note that the inputSchema has a type but no properties.

Flowise (https://github.com/FlowiseAI/Flowise) fails silently on this issue (something we'll need to address). For our setup, unless we patch Flowise, this means we can not use GraphQL queries without input arguments.

I'm hoping this repo can fix the issue of having inputs without the property field set.