Simon Willison’s Weblog

I like publishing transcripts of local Claude Code sessions using my claude-code-transcripts tool but I'm often paranoid that one of my API keys or similar secrets might inadvertently be revealed in the detailed log files.

I built this new Python scanning tool to help reassure me. You can feed it secrets and have it scan for them in a specified directory:

uvx scan-for-secrets $OPENAI_API_KEY -d logs-to-publish/

If you leave off the -d it defaults to the current directory.

It doesn't just scan for the literal secrets - it also scans for common encodings of those secrets e.g. backslash or JSON escaping, as described in the README.

If you have a set of secrets you always want to protect you can list commands to echo them in a ~/.scan-for-secrets.conf.sh file. Mine looks like this:

llm keys get openai
llm keys get anthropic
llm keys get gemini
llm keys get mistral
awk -F= '/aws_secret_access_key/{print $2}' ~/.aws/credentials | xargs

I built this tool using README-driven-development: I carefully constructed the README describing exactly how the tool should work, then dumped it into Claude Code and told it to build the actual tool (using red/green TDD, naturally.)