agent-card-diff-action reads the AgentCard JSON file at the workflow's checkout HEAD, retrieves the previous version via git show, posts a single PR comment via the GitHub API (when run on a pull_request event with a valid token), and writes structured outputs. No remote fetch beyond the GitHub API comment call, no execution of user-supplied code.
The action uses ${{ github.token }} by default — scoped to the repository where the workflow runs and never persisted. If you provide your own token via the github-token input, ensure it has only pull-requests: write permissions.
The git show invocation runs in a sub-shell with stdout-only piping; the previous file content is parsed as JSON without eval or Function().
Only the latest tagged release is supported.
Please use GitHub Security Advisories for private disclosure:
Do not file public issues for security reports.