GitHub Action Trigger MCP Server

Instructions

Implementation Reference

• src/index.ts:380-525 (handler)

  The core handler function that implements the enable_pull_request_automerge tool logic. It uses GitHub GraphQL API to first fetch the PR details, check status, and then enable auto-merge if not already enabled.
  async function enablePullRequestAutoMerge(owner: string, repo: string, pullNumber: number, mergeMethod: string = 'MERGE', token?: string) { // Use provided token or fall back to config token const authToken = token || config.githubToken; if (!authToken) { throw new Error('GitHub token is required to enable pull request auto-merge'); } try { const headers: Record<string, string> = { 'Accept': 'application/vnd.github+json', 'Authorization': `Bearer ${authToken}`, 'Content-Type': 'application/json' }; // First, get the pull request ID using GraphQL const getPullRequestIdQuery = { query: ` query GetPullRequestId($owner: String!, $repo: String!, $number: Int!) { repository(owner: $owner, name: $repo) { pullRequest(number: $number) { id title state autoMergeRequest { enabledAt mergeMethod } } } } `, variables: { owner: owner, repo: repo, number: pullNumber } }; const pullRequestResponse = await axios.post( 'https://api.github.com/graphql', getPullRequestIdQuery, { headers } ); if (pullRequestResponse.data.errors) { throw new Error(`GraphQL error: ${JSON.stringify(pullRequestResponse.data.errors)}`); } const pullRequest = pullRequestResponse.data.data?.repository?.pullRequest; if (!pullRequest) { throw new Error(`Pull request #${pullNumber} not found in ${owner}/${repo}`); } if (pullRequest.state !== 'OPEN') { throw new Error(`Pull request #${pullNumber} is not open (current state: ${pullRequest.state})`); } // Check if auto-merge is already enabled if (pullRequest.autoMergeRequest) { return { success: true, message: 'Auto-merge is already enabled for this pull request', pullRequest: { id: pullRequest.id, title: pullRequest.title, number: pullNumber, autoMergeEnabled: true, enabledAt: pullRequest.autoMergeRequest.enabledAt, mergeMethod: pullRequest.autoMergeRequest.mergeMethod } }; } const pullRequestId = pullRequest.id; // Now enable auto-merge using the mutation const enableAutoMergeMutation = { query: ` mutation EnablePullRequestAutoMerge($pullRequestId: ID!, $mergeMethod: PullRequestMergeMethod!) { enablePullRequestAutoMerge(input: { pullRequestId: $pullRequestId, mergeMethod: $mergeMethod }) { pullRequest { id title number autoMergeRequest { enabledAt mergeMethod } } } } `, variables: { pullRequestId: pullRequestId, mergeMethod: mergeMethod } }; const enableResponse = await axios.post( 'https://api.github.com/graphql', enableAutoMergeMutation, { headers } ); if (enableResponse.data.errors) { throw new Error(`Failed to enable auto-merge: ${JSON.stringify(enableResponse.data.errors)}`); } const result = enableResponse.data.data?.enablePullRequestAutoMerge?.pullRequest; if (!result) { throw new Error('Unexpected response from GitHub API'); } return { success: true, message: 'Auto-merge enabled successfully', pullRequest: { id: result.id, title: result.title, number: result.number, autoMergeEnabled: true, enabledAt: result.autoMergeRequest.enabledAt, mergeMethod: result.autoMergeRequest.mergeMethod } }; } catch (error) { if (axios.isAxiosError(error)) { const statusCode = error.response?.status; const errorMessage = error.response?.data?.message || error.message; if (statusCode === 401 || statusCode === 403) { throw new Error(`Authentication failed: ${errorMessage}. Make sure your token has the required permissions.`); } else if (statusCode === 404) { throw new Error(`Repository or pull request not found: ${errorMessage}`); } throw new Error(`GitHub API error: ${statusCode} - ${errorMessage}`); } throw error; } }
• src/index.ts:216-246 (schema)

  Input schema definition for the enable_pull_request_automerge tool, specifying parameters like owner, repo, pull_number, merge_method, and token.
  { name: "enable_pull_request_automerge", description: "Enable auto-merge for a specific pull request. This will automatically merge the PR when all required checks pass.", inputSchema: { type: "object", properties: { owner: { type: "string", description: "Owner of the repository (username or organization)" }, repo: { type: "string", description: "Name of the repository" }, pull_number: { type: "number", description: "The pull request number" }, merge_method: { type: "string", description: "The merge method to use when auto-merging (MERGE, SQUASH, or REBASE)", enum: ["MERGE", "SQUASH", "REBASE"] }, token: { type: "string", description: "GitHub personal access token (optional)" } }, required: ["owner", "repo", "pull_number"] } }
• src/index.ts:837-872 (registration)

  The registration and dispatching logic in the MCP CallToolRequestSchema handler that extracts arguments and calls the enablePullRequestAutoMerge function.
  case "enable_pull_request_automerge": { const owner = String(request.params.arguments?.owner); const repo = String(request.params.arguments?.repo); const pullNumber = Number(request.params.arguments?.pull_number); const mergeMethod = request.params.arguments?.merge_method ? String(request.params.arguments?.merge_method) : 'MERGE'; const token = request.params.arguments?.token ? String(request.params.arguments?.token) : undefined; if (!owner || !repo || !pullNumber) { throw new Error("Owner, repo, and pull_number are required"); } if (isNaN(pullNumber) || pullNumber <= 0) { throw new Error("pull_number must be a valid positive integer"); } const validMergeMethods = ['MERGE', 'SQUASH', 'REBASE']; if (!validMergeMethods.includes(mergeMethod)) { throw new Error(`merge_method must be one of: ${validMergeMethods.join(', ')}`); } try { const result = await enablePullRequestAutoMerge(owner, repo, pullNumber, mergeMethod, token); return { content: [{ type: "text", text: JSON.stringify(result, null, 2) }] }; } catch (error) { if (error instanceof Error) { throw new Error(`Failed to enable pull request auto-merge: ${error.message}`); } throw error; } }