GitHub

Connect Cardinal to GitHub so the AI agent can search code, browse repositories, query issues and pull requests, track deployments, and — with your approval — open issues and pull requests.

Overview

With the GitHub integration, the AI agent can:

• Search code across your organization’s repositories
• Browse repositories — view files, directory structure, and README content
• Query issues and pull requests — find open bugs, review PR status, and track project progress
• Analyze deployments — understand what was recently shipped
• Open issues and PRs, and comment — write actions are always gated behind human approval

Cardinal authenticates to GitHub as a GitHub App — a bot identity using short-lived, auto-rotated installation tokens scoped per repository. Access isn’t tied to any one person’s account, so it survives employee turnover, and Cardinal UI is the sole holder of the app’s private key (the MCP gateway only ever receives a freshly minted token).

Using Cardinal SaaS (app.cardinalhq.io)? There’s nothing to register. In Settings → Integrations → GitHub, click Connect GitHub App, approve the installation on GitHub, and choose your repositories. The rest of this page covers self-hosted Cardinal UI, where you register your own GitHub App once.

Capabilities

Self-hosted setup

Self-hosted Cardinal UI uses its own GitHub App. The hosted Cardinal app’s redirect and webhook callbacks point at app.cardinalhq.io, so they would never reach your Cardinal UI — you register an app whose callbacks point at your own Cardinal UI URL instead. This is also the only option for GitHub Enterprise Server (GHES): a github.com app cannot be installed on a GHES org.

You do this once per deployment. Afterward, org owners connect the integration from the UI with no further GitHub admin work.

Prerequisites

• Cardinal UI reachable at a stable HTTPS URL set as MAESTRO_BASE_URL — this is the base of the GitHub callbacks.
• The installing admin’s browser can reach that URL (the setup step is a browser redirect; Cardinal UI does not need to be internet-facing).
• For GHES, the host’s API URL (https://<ghe-host>/api/v3) must be listed in MAESTRO_GITHUB_ALLOWED_API_BASE_URLS.
• LICENSE_SIGNING_KEYS_PATH configured (already required for Cardinal UI) — the app private key is envelope-encrypted at rest with these keys.

1. Register the GitHub App

On github.com go to Settings → Developer settings → GitHub Apps → New GitHub App (register it under your org to own it there). On GHES, the equivalent path lives under your enterprise/org settings.

Identity

Setup URL — where GitHub returns the admin’s browser after install:

https://<your-maestro-base-url>/api/github-app/setup

• Check Redirect on update.
• Leave Request user authorization (OAuth) during installation OFF. Cardinal UI uses bot identity only — there is no OAuth client secret.

Webhook — optional. Leave Active unchecked. Cardinal UI finalizes installs and detects uninstalls by lazy reconcile on next use, so a webhook isn’t required and is awkward for an internal-only Cardinal UI (it would need GitHub’s servers to reach you inbound). Skip it unless you have a specific reason.

Repository permissions — grant exactly these (Read-only except where noted):

Comments on pull requests go through the Issues permission (GitHub models PR comments as issue comments), so no separate “PR comment” permission exists.

Subscribe to events: none required. (If you later enable webhooks, subscribe to installation and installation_repositories.)

Where can this app be installed: Only on this account is fine for a single-org install. Choose Any account only if you intend to install it across multiple orgs.

Create the app, then on its settings page:

1. Note the App ID.
2. Note the app slug (the name in the app’s URL, e.g. cardinal-acme).
3. Under Private keys, click Generate a private key and download the .pem. Store it securely — it is shown only once.

2. Install the app on your GitHub org

On the app’s settings page, click Install App and install it into your organization — or into a personal user account, both are supported — choosing All repositories or a specific selection. This creates the installation Cardinal UI acts through.

3. Connect it in Cardinal UI

1. Sign in to Cardinal UI as an org owner and go to Settings → Integrations.
2. Add a GitHub integration and enter:
   • App ID (from step 1)
   • App slug
   • Private key — paste the full contents of the .pem, including the -----BEGIN... / -----END... lines. It is write-only: sealed on save and never shown again.
   • API Base URL — leave empty for github.com; for GHES set https://<ghe-host>/api/v3.
3. Start the connect flow. Cardinal UI redirects you to GitHub; pick the organization or personal account to install into and approve the installation. GitHub returns your browser to the setup URL, and Cardinal UI verifies the installation directly with GitHub (it never trusts the redirect’s installation_id) before finalizing.
4. Select the Default Repositories the agent should search (optional but recommended), and fill in Name, Description, and Planner Hint as needed.

Once finalized, org owners can manage repositories from the UI without touching GitHub admin again.

What this enables

Once configured, you can ask the AI agent questions like:

• “Find where the rate limiter is implemented”
• “Show me open PRs for the payments service”
• “What issues were closed this sprint?”
• “What changed in the last deployment?”

Troubleshooting