Agent skill · product strategy · wshobson
signed-audit-trails-recipe
Step-by-step cookbook for setting up cryptographically signed audit trails on Claude Code tool calls. Use when explaining, evaluating, or demonstrating the pattern before committing to the protect-mcp runtime hooks. Covers Cedar policy, Ed25519 receipts, offline verification, tamper detection, CI/CD integration, and SLSA composition.
Why this skill is useful
Adds a comprehensive cookbook for implementing cryptographically signed audit trails with specific commands and policies that the AI wouldn't generate on its own.
What it needs
Requires protect-mcp installed locally. About 6k tokens when loaded. Last updated 2026-08-05. 38,570 stars on the source repository.
What this skill does
Signed Audit Trails for Claude Code Tool Calls 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. What this gives you Every tool call (Bash, Edit, Write, WebFetch) is: 1. Evaluated against a Cedar policy before execution. If the policy denies the call, the tool does not run. 2. Signed as an Ed25519 receipt after execution. Receipts are JCS-canonical, hash-chained, and verifiable offline by anyone with the public key. 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. When to use the pattern Regulated environments (finance, healthcare, critical infrastructure) where you need tamper-evident evidence of agent behavior CI/CD pipelines where you want to prove that a policy gate held for every automated build step Multi-party collaboration where a counterparty wants to verify your agent's behavior without trusting your operator Compliance contexts (EU AI Act Article 12, SLSA provenance for agent-built software) where standard logging is not sufficient Step 1: Install the hook configuration 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 publickey field); do not commit the private key. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills wshobson/signed-audit-trails-recipe