create_merge_request

Create a merge request to propose code changes from a source branch to a target branch in a GitLab project, enabling code review and integration.

Instructions

Create a new merge request

Input Schema

TableJSON Schema

Name	Required	Description
`project_id`	Yes	Project ID or path
`title`	Yes	Merge request title
`source_branch`	Yes	Source branch name
`target_branch`	Yes	Target branch name
`description`	No	Merge request description
`assignee_ids`	No	Array of user IDs to assign
`reviewer_ids`	No	Array of user IDs to review
`labels`	No	Comma-separated list of labels
`milestone_id`	No	Milestone ID

Implementation Reference

src/handlers/merge-requests.ts:219-248 (handler)

The main handler function in MergeRequestHandlers class that executes the create merge request logic by constructing the request payload and calling the GitLab API POST endpoint.

async createMergeRequest(args: CreateMergeRequestParams) {
  const requestData: any = {
    title: args.title,
    source_branch: args.source_branch,
    target_branch: args.target_branch,
  };

  if (args.description) {
    requestData.description = args.description;
  }

  if (args.assignee_ids) requestData.assignee_ids = args.assignee_ids;
  if (args.reviewer_ids) requestData.reviewer_ids = args.reviewer_ids;
  if (args.labels) requestData.labels = args.labels;
  if (args.milestone_id) requestData.milestone_id = args.milestone_id;

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

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

src/tools/merge-requests.ts:174-219 (schema)

MCP tool definition for 'create_merge_request' including the detailed inputSchema used for validation and documentation.

name: 'create_merge_request',
description: 'Create a new merge request',
inputSchema: {
  type: 'object',
  properties: {
    project_id: {
      type: 'string',
      description: 'Project ID or path',
    },
    title: {
      type: 'string',
      description: 'Merge request title',
    },
    source_branch: {
      type: 'string',
      description: 'Source branch name',
    },
    target_branch: {
      type: 'string',
      description: 'Target branch name',
    },
    description: {
      type: 'string',
      description: 'Merge request description',
    },
    assignee_ids: {
      type: 'array',
      items: { type: 'number' },
      description: 'Array of user IDs to assign',
    },
    reviewer_ids: {
      type: 'array',
      items: { type: 'number' },
      description: 'Array of user IDs to review',
    },
    labels: {
      type: 'string',
      description: 'Comma-separated list of labels',
    },
    milestone_id: {
      type: 'number',
      description: 'Milestone ID',
    },
  },
  required: ['project_id', 'title', 'source_branch', 'target_branch'],
},

src/types.ts:283-293 (schema)

TypeScript interface defining the input parameters for the createMergeRequest handler.

export interface CreateMergeRequestParams {
  project_id: string;
  title: string;
  source_branch: string;
  target_branch: string;
  description?: string;
  assignee_ids?: number[];
  reviewer_ids?: number[];
  labels?: string;
  milestone_id?: number;
}

src/server.ts:185-188 (registration)
Dispatch registration in the main server switch statement that routes 'create_merge_request' tool calls to the appropriate handler method.
```
case "create_merge_request":
  return await this.mergeRequestHandlers.createMergeRequest(
    args as unknown as CreateMergeRequestParams
  );
```

GitLab MCP Server