plugin CX Codex

signed-audit-trails — Claude Code plugin: audit and setup

Q: How do I install signed-audit-trails in Claude Code?

Run `/plugin marketplace add wshobson/agents`, then `/plugin install signed-audit-trails@claude-code-workflows`.

Learn how to sign records of Claude Code tool calls and detect tampering. Useful for evaluating the approach before adding runtime infrastructure.

Install into Claude Code · Plugin marketplace All methods and platforms ↓

/plugin marketplace add wshobson/agents
/plugin install signed-audit-trails@claude-code-workflows

Open on GitHub

What signed-audit-trails does

This is a teaching plugin, not a runtime hook. Its single file, skills/signed-audit-trails-recipe/SKILL.md, walks through configuring a Cedar policy and hooks, creating a first receipt, and demonstrating tamper detection. It also explains the receipt format and interoperability across implementations.

The examples use Ed25519 signatures and JCS canonicalization of JSON before signing. The walkthrough includes a GitHub Actions integration snippet and shows how receipts can be combined with SLSA provenance. For hooks that operate at runtime, you need the separate protect-mcp plugin; this one explains the pattern but does not intercept tool calls.

What it helps with

learn how signed records of tool calls work
set up a Cedar policy and create a receipt
demonstrate detection of a changed receipt
add receipt checks to GitHub Actions

Example prompts for the agent

Walk me through setting up Cedar and creating a signed receipt for a tool call.
Show how to detect a tampered receipt and verify its Ed25519 signature.
Draft an example of checking signed receipts in GitHub Actions.

How to install signed-audit-trails

Plugin marketplace

/plugin marketplace add wshobson/agents

/plugin install signed-audit-trails@claude-code-workflows

Step by step, with commands for each platform: Claude Code plugins: marketplaces, installing, and building your own

Questions about signed-audit-trails

How do I install signed-audit-trails in Claude Code?

Run /plugin marketplace add wshobson/agents, then /plugin install signed-audit-trails@claude-code-workflows.

What does signed-audit-trails do?

It teaches a workflow for signed audit records of Claude Code tool calls, covering Cedar policies, Ed25519 signatures, and tamper detection. It does not install runtime hooks.

Do I need protect-mcp to use signed-audit-trails?

No, the walkthrough can be used to learn the approach. For hooks that run during tool use, install the separate protect-mcp plugin.

Source text

signed-audit-trails · MIT

# signed-audit-trails

A teaching skill for setting up cryptographically signed audit trails on every
Claude Code tool call. Cookbook-style walkthrough with runnable examples.

## What this is

A **skill** (not a runtime hook): a set of instructions and examples that
explain the pattern end-to-end. Use this when you are figuring out whether
receipts are the right fit for your project. Once you know they are, install
the [`protect-mcp`](../protect-mcp/) plugin for the actual hooks.

## When to use this plugin

- **Learning** the pattern before committing to infrastructure
- **Evaluating** whether signed audit trails fit your compliance need
- **Teaching** team members the cryptographic model
  (JCS canonicalization + Ed25519 signatures)
- **Walking a client or auditor** through a live demonstration of tamper
  detection

For production use, the [`protect-mcp`](../protect-mcp/) plugin gives you the
runtime hooks directly. This plugin is the skill file you invoke via
`Skill` when you want the concept explained in-session.

## What is inside

```
skills/signed-audit-trails-recipe/SKILL.md
```

A single skill file containing:

- Step-by-step setup (Cedar policy, hook configuration, first receipt)
- Live tamper detection walkthrough
- Receipt format explanation (two invariants)
- Cross-implementation interoperability table
- CI/CD integration snippet (GitHub Actions)
- Composition with SLSA provenance for agent-built software
- Common pitfalls and references

## Standards

- **Ed25519** (RFC 8032) for receipt signatures
- **JCS** (RFC 8785) for deterministic JSON canonicalization before signing
- **Cedar** (AWS) for policy evaluation
- **IETF draft** [draft-farley-acta-signed-receipts](https://datatracker.ietf.org/doc/draft-farley-acta-signed-receipts/)

## Related plugins in this marketplace

- [`protect-mcp`](../protect-mcp/) — the runtime hook implementation
- [`review-agent-governance`](../review-agent-governance/) — require human
  approval before review-surface actions; composes with protect-mcp

## License

MIT. Same as the adjacent governance-category plugins in this marketplace.

Similar plugins

Plugins catalog →

discernment-nudge official anthropics This plugin adds two or three short follow-up questions after a substantive answer. Use it to check facts, probe reasoning, and spot missing context. ★ 183,839repo stars academy-guide official anthropics Recommends Claude Academy courses, tutorials, and use cases when you ask how to use Claude. It suits people learning Claude features through real tasks. ★ 183,839repo stars claude-api official anthropics This plugin adds Claude API and SDK guidance for building LLM-powered applications. Install it when your project needs a Claude integration. ★ 183,839repo stars example-skills official anthropics A collection of Claude skill examples for web testing, MCP work, design and documents. Use it to inspect skill structure or start a custom skill from a template. ★ 183,839repo stars document-skills official anthropics Adds Claude Code skills for creating and editing Word, Excel, PowerPoint, and PDF files. Install it when your agent needs to handle office documents. ★ 183,839repo stars superpowers obra The plugin guides an agent from task discussion and planning through subagent development, code review, debugging, and TDD. Use it when the workflow matters. CX Codex ★ 305,248repo stars

From the same set342

The whole set →