reply_to_mr_discussion

Add responses to merge request discussion threads to provide feedback, answer questions, or resolve comments during code review.

Instructions

Reply to an existing discussion thread on a merge request

Input Schema

TableJSON Schema

Name	Required	Description
`project_id`	Yes	Project ID or path
`merge_request_iid`	Yes	Merge request internal ID
`discussion_id`	Yes	The ID of the discussion to reply to
`body`	Yes	The content of the reply (supports Markdown)

Implementation Reference

src/handlers/merge-requests.ts:465-485 (handler)

The core handler function that executes the tool by posting a reply note to the specified GitLab merge request discussion via API.

async replyToMRDiscussion(args: ReplyToMRDiscussionParams) {
  const requestData = {
    body: args.body,
  };

  const data = await this.client.post(
    `/projects/${encodeURIComponent(args.project_id)}/merge_requests/${
      args.merge_request_iid
    }/discussions/${args.discussion_id}/notes`,
    requestData
  );

  return {
    content: [
      {
        type: "text",
        text: JSON.stringify(data, null, 2),
      },
    ],
  };
}

src/types.ts:507-512 (schema)

TypeScript interface defining the input parameters for the replyToMRDiscussion handler.

export interface ReplyToMRDiscussionParams {
  project_id: string;
  merge_request_iid: number;
  discussion_id: string;
  body: string;
}

src/tools/merge-requests.ts:469-494 (registration)

Tool registration including name, description, and input schema for MCP protocol.

{
  name: 'reply_to_mr_discussion',
  description: 'Reply to an existing discussion thread on a merge request',
  inputSchema: {
    type: 'object',
    properties: {
      project_id: {
        type: 'string',
        description: 'Project ID or path',
      },
      merge_request_iid: {
        type: 'number',
        description: 'Merge request internal ID',
      },
      discussion_id: {
        type: 'string',
        description: 'The ID of the discussion to reply to',
      },
      body: {
        type: 'string',
        description: 'The content of the reply (supports Markdown)',
      },
    },
    required: ['project_id', 'merge_request_iid', 'discussion_id', 'body'],
  },
},

src/server.ts:223-226 (registration)

Dispatch logic in server that routes the tool call to the merge request handler.

case "reply_to_mr_discussion":
  return await this.mergeRequestHandlers.replyToMRDiscussion(
    args as unknown as ReplyToMRDiscussionParams
  );

GitLab MCP Server