Accept Endpoints and Headers Sent from mcp-client

[takumiyoshikawa]

Summary

Hello, mcp-graphql is very easy to use, and I have been trying it out for the past few days.

Some backend platforms provide an interface that allows backend applications to be created via mcp. Because of this, I wanted to receive the endpoint and header information of applications created by mcp-client so that I could insert seed data and query data as needed.

My proposal is to provide a way to receive endpoints and headers for introspection and query execution.

Proposed Solution

I have already forked the repository and tested the proposed changes.
https://github.com/takumiyoshikawa/mcp-graphql/tree/feat/accept-graphql-info-from-client

If you like the implementation, I would be happy to submit a PR.
I would really appreciate your feedback!

[blurrah]

Hey thanks! Quickly checked and looks nice, you can always submit a PR. We might want to notify the model which headers are already set when starting the server.

[takumiyoshikawa]

Thanks, I will raise a PR and discuss this point!

We might want to notify the model which headers are already set when starting the server.

[blurrah]

Merged your PR and released it as 0.3.2, thanks for the help on this.

[mweidner037]

We might want to notify the model which headers are already set when starting the server.

I would argue that this is undesirable, given that your headers likely contain OAuth2 tokens / API keys. In particular, when using mcp-graphql alongside other MCP servers, one of the other servers could maliciously instruct the agent to send secrets read from mcp-graphql's introspect-schema endpoint. See "Shadowing Tool Descriptions with Multiple Servers" here.

More generally, allowing the agent to change the endpoint and headers may lead to surprising behavior - I would naively expect the claude_desktop_config.json settings to be hardcoded, but instead the agent is free to contact other GraphQL servers as it pleases.

If you don't want to revert #7 entirely, I'm happy to work on a compromise PR.

[blurrah]

Very good point. I will revert it on Monday once I can release it.

@takumiyoshikawa it's best if you fork it for yourself before the revert. Do take heed of the security issues if you want to continue this way. You can also always add multiple instances of this server and add context when to pick which.

[mweidner037]

Thank you @blurrah !