signed-audit-trails-recipe

Cookbook-style walkthrough for cryptographically signed receipts on every Claude Code tool call. This is the teaching skill. For the runtime implementation, install the protect-mcp plugin. Every tool call ( Bash , Edit , Write , WebFetch ) is: An auditor, regulator, or counterparty can verify the full chain later with a single CLI command ( npx @veritasacta/verify receipts/*.json ). No network call, no vendor lookup, no trust in the operator. Create .claude/settings.json in your project root: The first run of protect-mcp sign generates ./protect-mcp.key (Ed25519 private key) if one does not exist. Commit the public key fingerprint (visible in any receipt's public_key field); do not commit the private key. Add the private key and receipt directory to .gitignore : Create ./protect.cedar : Four rules: Cedar forbid rules take precedence over permit rules, so destructive commands cannot be bypassed by a later permissive rule.