Git Repo Browser MCP

Instructions

Implementation Reference

• src/handlers/branch-operations.js:12-77 (handler)

  The main handler function that executes the git_branch_diff tool. It clones the repository, ensures branches are available, computes the diff between source and target branches (with optional patch), gets commit count, and returns a JSON-formatted result or error.

  export async function handleGitBranchDiff({
    repo_url,
    source_branch,
    target_branch,
    show_patch = false,
  }) {
    try {
      const repoPath = await cloneRepo(repo_url);
      const git = simpleGit(repoPath);
  
      // Make sure both branches exist locally
      const branches = await git.branch();
      if (!branches.all.includes(source_branch)) {
        await git.fetch("origin", source_branch);
        await git.checkout(source_branch);
      }
  
      if (!branches.all.includes(target_branch)) {
        await git.fetch("origin", target_branch);
      }
  
      // Get the diff between branches
      const diffOptions = ["--name-status"];
      if (show_patch) {
        diffOptions.push("--patch");
      }
  
      const diff = await git.diff([
        ...diffOptions,
        `${target_branch}...${source_branch}`,
      ]);
  
      // Get commit range information
      const logSummary = await git.log({
        from: target_branch,
        to: source_branch,
      });
  
      const result = {
        commits_count: logSummary.total,
        diff_summary: diff,
      };
  
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify(result, null, 2),
          },
        ],
      };
    } catch (error) {
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify(
              { error: `Failed to get branch diff: ${error.message}` },
              null,
              2
            ),
          },
        ],
        isError: true,
      };
    }

• src/server.js:133-158 (schema)

  The MCP tool schema definition for 'git_branch_diff', including description and input schema with properties repo_url, source_branch, target_branch, and optional show_patch.

  name: "git_branch_diff",
  description:
    "Compare two branches and show files changed between them.",
  inputSchema: {
    type: "object",
    properties: {
      repo_url: {
        type: "string",
        description: "The URL of the Git repository",
      },
      source_branch: {
        type: "string",
        description: "The source branch name",
      },
      target_branch: {
        type: "string",
        description: "The target branch name",
      },
      show_patch: {
        type: "boolean",
        description: "Whether to include the actual diff patches",
        default: false,
      },
    },
    required: ["repo_url", "source_branch", "target_branch"],
  },

• src/server.js:902-902 (registration)

  Registers the tool name 'git_branch_diff' mapped to the handleGitBranchDiff handler function in the server's handlersMap.

  git_branch_diff: handleGitBranchDiff,

• src/handlers/index.js:14-19 (registration)

  Imports the handleGitBranchDiff handler from branch-operations.js into the handlers index module, facilitating its use in the server.

  import {
    handleGitBranchDiff,
    handleGitCheckoutBranch,
    handleGitDeleteBranch,
    handleGitMergeBranch,
  } from "./branch-operations.js";