update_merge_request

Modify an existing GitLab merge request by updating its title, description, state, target branch, labels, assignees, milestone, or source branch removal setting.

Instructions

Update an existing merge request in a GitLab project

Input Schema

TableJSON Schema

Name	Required	Description
`project_id`	Yes	Project ID or URL-encoded path
`merge_request_iid`	Yes	Merge request internal ID
`title`	No	New merge request title
`description`	No	New merge request description
`state_event`	No	Change merge request state
`target_branch`	No	New target branch
`labels`	No	Array of label names
`assignee_ids`	No	Array of user IDs to assign
`milestone_id`	No	Milestone ID to assign
`remove_source_branch`	No	Remove source branch when merged

Implementation Reference

src/api/merge-requests.ts:66-95 (handler)

The implementation of the update_merge_request API function, which calls the GitLab PUT endpoint to update a merge request.

export async function updateMergeRequest(
  projectId: string,
  mergeRequestIid: number,
  options: {
    title?: string;
    description?: string;
    state_event?: "close" | "reopen";
    target_branch?: string;
    labels?: string[];
    assignee_ids?: number[];
    milestone_id?: number;
    remove_source_branch?: boolean;
  }
): Promise<GitLabMergeRequest> {
  if (!projectId?.trim()) {
    throw new Error("Project ID is required");
  }
  if (!mergeRequestIid || mergeRequestIid < 1) {
    throw new Error("Valid merge request IID is required");
  }

  const endpoint = `/projects/${encodeProjectId(projectId)}/merge_requests/${mergeRequestIid}`;

  const mergeRequest = await gitlabPut<GitLabMergeRequest>(endpoint, {
    ...options,
    labels: options.labels?.join(",")
  });

  return GitLabMergeRequestSchema.parse(mergeRequest);
}

src/schemas.ts:475-483 (schema)

Input validation schema for the update_merge_request tool.

export const UpdateMergeRequestSchema = z.object({
  project_id: z.string().describe("Project ID or URL-encoded path"),
  merge_request_iid: z.number().describe("Merge request internal ID"),
  title: z.string().optional().describe("New merge request title"),
  description: z.string().optional().describe("New merge request description"),
  state_event: z.enum(["close", "reopen"]).optional().describe("Change merge request state"),
  target_branch: z.string().optional().describe("New target branch"),
  labels: z.array(z.string()).optional().describe("Array of label names"),
  assignee_ids: z.array(z.number()).optional().describe("Array of user IDs to assign"),

src/server.ts:425-430 (registration)

Handler registration and execution logic for the update_merge_request tool within the main server loop.

case "update_merge_request": {
  const args = UpdateMergeRequestSchema.parse(request.params.arguments);
  const { project_id, merge_request_iid, ...options } = args;
  const mergeRequest = await api.updateMergeRequest(project_id, merge_request_iid, options);
  return { content: [{ type: "text", text: JSON.stringify(mergeRequest, null, 2) }] };
}

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