whygit MCPサーバー

whygit

What just happened to my Git repository, and how do I fix it?

whygit looks at a Git repository and tells you, in plain English, what state it is in and which commands will get you out of it: a merge conflict, a rebase stopped halfway, a detached HEAD, a rejected push, a login GitHub won't accept, a 120 MB CSV that GitHub will refuse. Paste it an error message and it explains that too.

It is written for people meeting Git for the first time. Git's own messages are accurate but hard to read; whygit turns them into a short explanation and the exact fix.

It only ever reads your repository. It never runs the fixes it suggests, so you stay in control and learn the commands as you go.

There are two ways to use it, built on the same engine:

• On the command line, with no AI tools involved: whygit.
• As an MCP server, so an assistant such as Claude Code, Claude Desktop or Cursor gets a reliable diagnosis instead of guessing from git status.

Install

whygit needs Python 3.10 or newer and Git. Pick one:

uv tool install whygit     # with uv (https://docs.astral.sh/uv/)
pipx install whygit        # with pipx
uvx whygit                 # run once without installing

This works the same on macOS, Windows and Linux.

Use it from the terminal

Run it inside your project folder:

whygit                    # what's wrong here, most urgent first
whygit status             # a plain summary: branch, upstream, what's changed
whygit explain "fatal: refusing to merge unrelated histories"
git push 2>&1 | whygit explain -

Options: --path <folder> (or -C) to look at another folder, --json for machine-readable output, --no-color to turn off colour. Colour is only used in a real terminal and never when NO_COLOR is set.

Exit codes: 0 nothing blocking, 1 something blocking was found, 2 bad usage (for example the folder does not exist), 3 explain did not recognise the message.

Example

$ whygit
whygit: /Users/sam/ds3500/hw2 (branch main)

[BLOCKING] Merge in progress with conflicts in 1 file
  Git tried to combine two lines of work, but both changed the same part of these
  files, so it stopped and is waiting for you to choose what the result should be.
  Nothing is lost while you decide.
  Conflicted files:
    - analysis.py  (both changed)
  How to fix:
    Finish the merge:
      1. Open each file and find the blocks between <<<<<<< and >>>>>>>. The part
         above ======= is one version, the part below is the other. Keep what you
         want, and delete the three marker lines.
      2. git add analysis.py
         Marks the files as resolved
      3. git commit --no-edit
         Records the merge and finishes it
    Or cancel the merge:
      1. git merge --abort
         Puts everything back the way it was before the merge started
  Learn more: https://git-scm.com/docs/git-merge#_how_to_resolve_conflicts

1 blocking. whygit never runs these commands for you; copy the ones you want.

Commands that can lose work (git restore, git rebase --skip, git push --force-with-lease and so on) are always marked with a warning, and a safer option is listed first when one exists.

Use it with an AI assistant (MCP)

whygit mcp runs a Model Context Protocol server over stdio with three read-only tools:

Tool	Use it when	Returns
diagnose_repo(path=".")	something seems stuck or broken	every problem found, most urgent first, with explanation and fix
explain_git_error(error_text, path=None)	a git command printed an error	what the error means and the fix, using the repository's state if path is given
explain_state(path=".")	you want a neutral summary	branch, upstream, ahead/behind, remotes, staged and changed files, operations in progress

Results are small JSON objects. Pass an absolute path: relative paths resolve against the server's working directory, which for desktop apps is usually not your project. ~ works.

Claude Code

claude mcp add --scope user whygit -- uvx whygit mcp

--scope user makes it available in every project; leave it out to add it to the current project only. Check it with claude mcp list.

Claude Desktop

Open Settings > Developer > Edit Config, and add whygit to claude_desktop_config.json (on macOS ~/Library/Application Support/Claude/, on Windows %APPDATA%\Claude\):

{
  "mcpServers": {
    "whygit": {
      "command": "uvx",
      "args": ["whygit", "mcp"]
    }
  }
}

Restart Claude Desktop. If it can't find uvx, use the full path that which uvx (macOS) or where uvx (Windows) prints as the command.

Cursor

Add the same block to ~/.cursor/mcp.json (all projects) or .cursor/mcp.json in a project:

{
  "mcpServers": {
    "whygit": {
      "command": "uvx",
      "args": ["whygit", "mcp"]
    }
  }
}

If you installed whygit with uv tool install or pipx, you can use "command": "whygit" with "args": ["mcp"] instead.

What it recognises

Repository states: merge conflicts (and a merge that is resolved but not committed, including leftover <<<<<<< markers), a rebase stopped on a conflict or an edit, cherry-pick, revert, git am and bisect in progress, detached HEAD (and commits that no branch points to), diverged / behind / ahead of the upstream, no upstream yet (the first git push -u), no remote, upstream branch deleted, no commits yet, not a repository (including being one folder too high, and your home folder), a home folder that was accidentally turned into a repository, nested repositories (common with downloaded starter code), files over GitHub's 100 MB limit (and over 50 MB) staged or in unpushed commits, files that usually hold secrets (.env, id_rsa, *.pem, kaggle.json, credentials JSON), notebooks with large saved outputs, Jupyter notebook conflicts, missing user.name / user.email, a leftover index.lock, and folders Git refuses because of "dubious ownership".

Error messages: rejected pushes, "You have divergent branches", "refusing to merge unrelated histories", GitHub login failures (passwords no longer work; it explains tokens, SSH and gh auth login, and never asks for your token), Permission denied (publickey), repository not found, 403, "Your local changes would be overwritten", untracked files in the way, "not a git repository", "src refspec main does not match any", "pathspec did not match", "remote origin already exists", missing upstream, "couldn't find remote ref", GitHub's large-file rejection (GH001), "detected dubious ownership", "Please tell me who you are", index.lock exists, line-ending warnings, network errors, and more. If it doesn't recognise a message, it says so and shows what it can see in the repository instead.

The read-only promise

whygit never changes your repository, and this is enforced in code rather than left to good intentions:

• Every Git command goes through a single function that only accepts read-only subcommands (status, rev-parse, for-each-ref, rev-list, diff, log, ls-files, cat-file, config --get, remote -v, ...) and refuses anything else, including the writing forms of config, remote and symbolic-ref.
• It sets GIT_OPTIONAL_LOCKS=0, so even git status doesn't refresh the index, and turns off external diff programs and the fsmonitor hook.
• It never runs git fetch. Ahead/behind counts are "as of your last fetch", and whygit tells you to run git fetch yourself when that matters.
• The test suite builds each state in a real repository, snapshots every file under .git (names, timestamps and contents) before and after diagnosing, and checks nothing changed. It also checks that no other module in the package can start a process or write a file.

Credentials are never printed: a remote address like https://name:token@github.com/... is shown as https://***@github.com/..., in every output.

Privacy

whygit collects nothing and makes no network calls. It reads your repository on your own computer and prints the result. That's all.

Licence

MIT. Copyright (c) 2026 Kameswara Sai Srikar Manda.