GitLab MCP Server

Instructions

Implementation Reference

• src/handlers/merge-requests.ts:580-620 (handler)

  Core implementation of the mark_mr_as_draft tool: fetches the MR details, checks if already marked as draft (Draft: or WIP: prefix), and if not, updates the title by prefixing 'Draft: '.

  async markMRAsDraft(args: MarkMRAsDraftParams) {
    // First get the current MR to check its title
    const mr = (await this.client.get(
      `/projects/${encodeURIComponent(args.project_id)}/merge_requests/${
        args.merge_request_iid
      }`
    )) as GitLabMergeRequest;
  
    // Check if already a draft
    if (mr.title.startsWith("Draft: ") || mr.title.startsWith("WIP: ")) {
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify(
              { message: "Merge request is already marked as draft", ...mr },
              null,
              2
            ),
          },
        ],
      };
    }
  
    // Update the title to add Draft: prefix
    const data = await this.client.put(
      `/projects/${encodeURIComponent(args.project_id)}/merge_requests/${
        args.merge_request_iid
      }`,
      { title: `Draft: ${mr.title}` }
    );
  
    return {
      content: [
        {
          type: "text",
          text: JSON.stringify(data, null, 2),
        },
      ],
    };
  }

• src/tools/merge-requests.ts:621-639 (registration)

  Tool registration: defines the MCP tool object with name 'mark_mr_as_draft', description, and input JSON schema. Included in mergeRequestTools array imported for server tool listing.

  {
    name: 'mark_mr_as_draft',
    description:
      'Mark a merge request as draft (work in progress, not ready for review)',
    inputSchema: {
      type: 'object',
      properties: {
        project_id: {
          type: 'string',
          description: 'Project ID or path',
        },
        merge_request_iid: {
          type: 'number',
          description: 'Merge request internal ID',
        },
      },
      required: ['project_id', 'merge_request_iid'],
    },
  },

• src/server.ts:247-250 (registration)

  Server dispatch: switch case in CallToolRequestSchema handler that routes calls to the tool to MergeRequestHandlers.markMRAsDraft method.

  case "mark_mr_as_draft":
    return await this.mergeRequestHandlers.markMRAsDraft(
      args as unknown as MarkMRAsDraftParams
    );

• src/types.ts:543-546 (schema)

  TypeScript type definition for the input parameters used by the handler and referenced in server dispatch.

  export interface MarkMRAsDraftParams {
    project_id: string;
    merge_request_iid: number;
  }