GitLab MCP Server

MCP (Model Context Protocol) server for AI-assisted code review with GitLab on-premise instances.

Features

Merge Request Tools

• List, get, create merge requests
• Get MR changes, commits, pipelines
• Get and add discussions/comments
• Approve, unapprove, merge MRs

Repository Tools

• List projects
• Browse repository tree
• Get file content and blame
• Search code
• List branches and commits

Security Model

Uses OAuth with intersection-based access control:

• User authenticates via GitLab OAuth
• AI access limited to repos both user AND service account can access
• All API calls made with service account token for audit trail

Prerequisites

• Python 3.11+
• GitLab instance with OAuth application configured
• SSL certificate for HTTPS

Setup

1. GitLab OAuth Application

Create in GitLab Admin > Applications:

• Redirect URI: https://<server-host>:<port>/oauth/callback
• Scopes: read_user, read_api, read_repository, api (for write operations)
• Confidential: Yes

2. Secrets File

Create a JSON file with credentials:

{
  "oauth_client_id": "<gitlab-oauth-app-id>",
  "oauth_client_secret": "<gitlab-oauth-app-secret>",
  "service_token": "<service-account-personal-access-token>"
}

3. Environment Variables

Variable	Required	Description
GITLAB_URL	yes	GitLab instance URL
GITLAB_SECRETS_PATH	yes	Path to secrets JSON file
MCP_SERVER_BASE_URL	yes	Server URL with https and port (e.g., https://localhost:8443)
MCP_SSL_CERT_PATH	yes	Path to SSL certificate
MCP_SSL_KEY_PATH	yes	Path to SSL private key
SSL_CERT_FILE	no	CA certificate for GitLab (self-signed certs)

4. Install

pip install .

Running

gitlab-mcp

Development

pip install -e ".[dev]"
pytest