Environment variables indicative of coding agents

These might be useful to block or otherwise indicate things to LLM coding agents when they encounter your project, for example refusing to build or run tests, or telling the agent it’s performing copyright infringement (which appears to be effective in causing them to bail).

The below is a list of environment variables highly indicative of LLM agents. There are other methods, such as traversing /proc to find parents.

Please email me with additions.

OpenAI Codex

Claude Code