Skip to content

feat: enable tool access to HTTP request headers #175

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 1 commit into
base: main
Choose a base branch
from

Conversation

sahra-karakoc
Copy link

Motivation and Context

HTTP request headers weren't available in the tool context
Related: #153

How Has This Been Tested?

With an example header extractor

Breaking Changes

No

Types of changes

  • Bug fix (non-breaking change which fixes an issue)
  • New feature (non-breaking change which adds functionality)
  • Breaking change (fix or feature that would cause existing functionality to change)
  • Documentation update

Checklist

  • I have read the MCP Documentation
  • My code follows the repository's style guidelines
  • New and existing tests pass locally
  • I have added appropriate error handling
  • I have added or updated documentation as needed

Additional context

@@ -84,8 +84,8 @@ async fn post_handler(
.ok_or((StatusCode::NOT_FOUND, "session not found").into_response())?;
session.handle().clone()
};
// inject request part
message.insert_extension(parts);
let headers_to_insert: http::HeaderMap = parts.headers.clone();
Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I prefer to inject whole request part, in case of people want to get other information like request uri or other data in http::Extensions

use rmcp::handler::server::tool::{FromToolCallContextPart, ToolCallContext};

#[derive(Debug)]
pub struct ReqHeaders(pub HeaderMap);
Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I prefer to use HttpReqHeaders or HttpRequestHeaders as its ident.

@Hendler
Copy link
Contributor

Hendler commented May 16, 2025

Do other MCP server implementations allow header access? I find this a useful feature and had a hard time gaining access to the headers in FastMCP python. Had to monkey patch.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

Successfully merging this pull request may close these issues.

3 participants