ghapp-mcp-server

ghapp is the GitHub server for Straza. It lets AI agents work on GitHub through MCP as one GitHub App: each call reaches one repo, with only the permissions its tool needs, and no GitHub token ever sits on the agent's machine.

ghapp is of no use without Straza. Straza decides which repos each agent may touch, and brings the grant that opens git. Without it, ghapp would reach every repo the App is installed on, and git would not work at all. If you don't run Straza, use GitHub's official MCP server, github/github-mcp-server, instead.

MCP is the protocol AI agents use to call tools. Straza is the gateway in front of MCP servers: its roles say which tools and repos an agent may use. ghapp holds the GitHub App's private key and makes a short-lived GitHub token for each call. GitHub sees every action as ghapp[bot].

A tool call

Two locks. Straza decides whether the agent's role covers the repo, and a repo no role covers stops there. ghapp then makes sure the call can touch only that repo: it checks who is calling, that the name is exact and that the repo id is the approved one, and makes a token for that one repo with only the tool's permissions.

git push

The agent types plain git push. Straza's holder, a service on the same machine under its own OS account, gets a grant for exactly that branch and those commits, and sends the push to ghapp with the grant and a proof signed by its own key. ghapp checks both, compares the push with the grant, and streams it to GitHub with a token that stays in ghapp. A push can be 2 GiB, so the code never goes through MCP.

Over MCP, git_push and git_fetch only check the repo and give the plain git command. Only the holder's grant opens git.

Tools

repo_list, repo_get, branch_list, file_get, pr_list, pr_get, pr_create, pr_comment, pr_merge, issue_list, issue_get, issue_create, issue_comment, search_code and search_issues, and for git git_fetch and git_push. Each names one repo as owner/name, exactly as GitHub spells it. GHAPP_MCP_READ_ONLY=true leaves out the tools that write.

Install

The container image, for linux/amd64 and linux/arm64:

docker pull ghcr.io/strazahq/ghapp-mcp-server:0.1.1

A release binary for Linux, macOS or Windows, checked against the release's checksums and its signed build provenance:

v=0.1.0
f=ghapp-mcp-server_${v}_linux_amd64.tar.gz
base=https://github.com/strazahq/ghapp-mcp-server/releases/download/v$v
curl -fsSLO "$base/$f" -O "$base/SHA256SUMS"
sha256sum --check --ignore-missing SHA256SUMS
gh attestation verify "$f" --owner strazahq
tar -xzf "$f"

Each archive also has a signed SPDX SBOM: gh attestation verify "$f" --owner strazahq --predicate-type https://spdx.dev/Document/v2.3.

With Go:

go install github.com/strazahq/ghapp-mcp-server@v0.1.0

Then create the GitHub App: [docs/githu

... View full README on GitHub