How can I distinguish between pull requests from AI coding agents like Claude Code and human developers?

Verdict: You cannot reliably tell them apart from the PR author alone. Look at the bot account type first, then at commit trailers.

Signals by scenario

1. Check the account type for hosted agents.

• The REST events schema lists type with the values Bot, User and Organization (GitHub REST events).
• Bot accounts for GitHub Apps use a [bot] login suffix. I did not confirm this in the docs I read, so verify it on a real PR.
• GitHub's Claude coding agent is a third-party agent. Enabling it installs a GitHub App named anthropic code agent (About third-party coding agents).
• That app's actions appear in the audit log. The app does not appear in your account's list of GitHub App installations, so check the audit log, not the installed apps list.

2. Check commit trailers for local agents.

• Git reads trailers from the block at the end of a commit message (git-interpret-trailers). Trailers are a convention, not an identity check. Anyone can write them.
• GitHub's Co-authored-by trailer attributes a commit to more than one person. It counts toward a contribution only if the email matches a GitHub account (Creating a commit with multiple authors).
• The Linux kernel asks for an Assisted-by: LLM [TOOL] trailer. It also forbids AI agents from adding Signed-off-by (Linux kernel AI coding assistants guide).
• I did not verify whether Claude Code adds any trailer by default. Check a few of its commits in your repository before you rely on this.

What does not work

• Author name or email. A local agent commits under the developer's identity.
• PR description text. Anyone can write "generated by Claude" in a PR.
• Bot-looking names. A human can use a bot-style name, and a bot can use a human-looking one.

Recommendation

1. Filter PRs by type == Bot to find hosted agents.
2. Scan commit messages for Co-authored-by and Assisted-by trailers to find local agents. Treat a missing trailer as "unknown", not "human".
3. Require a human sign-off on any PR that matches an agent signal.

Choose the bot-account check if: the agent runs in the cloud or as a GitHub App. Choose the trailer check if: developers run agents on their own machines.

If you want agent commits to carry a verifiable record, githug does this. Its agents commit under their own identity. Agent commits carry trailers that name the accountable human, the agent and the run. The hug CLI sets this up and is free during the beta. Checks are available at githug.ai/v or through the githug-ai/verify GitHub Action.