create_merge_request

Generate a new merge request in a GitLab project by specifying source and target branches, title, description, and project details.

Instructions

Create a new merge request in a GitLab project

Input Schema

TableJSON Schema

Name	Required	Description	Default
`allow_collaboration`	No
`description`	No
`draft`	No
`project_id`	No
`source_branch`	No
`target_branch`	No
`title`	No

Implementation Reference

src/index.ts:144-148 (registration)

Registration of the 'create_merge_request' tool in the ALL_TOOLS array, including name, description, input schema, and read-only flag.

{
  name: "create_merge_request",
  description: "Create a new merge request in a GitLab project",
  inputSchema: createJsonSchema(CreateMergeRequestSchema),
  readOnly: false

src/index.ts:408-412 (handler)

MCP tool handler in the switch statement: parses arguments with CreateMergeRequestSchema, extracts project_id and options, calls gitlabApi.createMergeRequest, and returns JSON response.

case "create_merge_request": {
  const args = CreateMergeRequestSchema.parse(request.params.arguments);
  const { project_id, ...options } = args;
  const mergeRequest = await gitlabApi.createMergeRequest(project_id, options);
  return { content: [{ type: "text", text: JSON.stringify(mergeRequest, null, 2) }] };

src/schemas.ts:426-428 (schema)
CreateMergeRequestSchema definition, which merges project_id with CreateMergeRequestOptionsSchema for input validation.
```
export const CreateMergeRequestSchema = z.object({
  project_id: z.string()
}).merge(CreateMergeRequestOptionsSchema);
```

src/schemas.ts:382-389 (schema)

CreateMergeRequestOptionsSchema defining input fields: title, description, source_branch, target_branch, allow_collaboration, draft.

export const CreateMergeRequestOptionsSchema = z.object({
  title: z.string(),
  description: z.string().optional(),
  source_branch: z.string(),
  target_branch: z.string(),
  allow_collaboration: z.boolean().optional(),
  draft: z.boolean().optional()
});

src/gitlab-api.ts:728-780 (handler)

Core implementation of createMergeRequest in GitLabApi class: makes POST request to GitLab API to create merge request and parses response.

async createMergeRequest(
  projectId: string,
  options: z.infer<typeof CreateMergeRequestOptionsSchema>
): Promise<GitLabMergeRequest> {
  const response = await fetch(
    `${this.apiUrl}/projects/${encodeURIComponent(projectId)}/merge_requests`,
    {
      method: "POST",
      headers: {
        "Authorization": `Bearer ${this.token}`,
        "Content-Type": "application/json"
      },
      body: JSON.stringify({
        title: options.title,
        description: options.description,
        source_branch: options.source_branch,
        target_branch: options.target_branch,
        allow_collaboration: options.allow_collaboration,
        draft: options.draft
      })
    }
  );

  if (!response.ok) {
    throw new McpError(
      ErrorCode.InternalError,
      `GitLab API error: ${response.statusText}`
    );
  }

  const responseData = await response.json() as Record<string, any>;

  return {
    id: responseData.id,
    iid: responseData.iid,
    project_id: responseData.project_id,
    title: responseData.title,
    description: responseData.description || null,
    state: responseData.state,
    merged: responseData.merged,
    author: responseData.author,
    assignees: responseData.assignees || [],
    source_branch: responseData.source_branch,
    target_branch: responseData.target_branch,
    diff_refs: responseData.diff_refs || null,
    web_url: responseData.web_url,
    created_at: responseData.created_at,
    updated_at: responseData.updated_at,
    merged_at: responseData.merged_at,
    closed_at: responseData.closed_at,
    merge_commit_sha: responseData.merge_commit_sha
  };
}

gitlab-mcp-server