# Garl > AI agent trust & reputation protocol — verify, score, route, compare, delegate. 18 tools. - **Type:** MCP server - **Install:** `agentstack add mcp-garl-protocol-garl` - **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior - **Seller:** [Garl-Protocol](https://agentstack.voostack.com/s/garl-protocol) - **Installs:** 0 - **Category:** [AI & ML](https://agentstack.voostack.com/c/ai-and-ml) - **Latest version:** 1.1.3 - **License:** Apache-2.0 - **Upstream author:** [Garl-Protocol](https://github.com/Garl-Protocol) - **Source:** https://github.com/Garl-Protocol/garl - **Website:** https://garl.ai ## Install ```sh agentstack add mcp-garl-protocol-garl ``` Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent. ## About GARL Protocol Signed, verifiable receipts for everything your AI agents do. Every action an AI agent takes — code commits, tool calls, API calls, payments — gets a signed receipt.GARL signs each one with ECDSA-secp256k1 (RFC 6979 deterministic) and anchors it on Base mainnet, so anyone can verify what an agent did, offline, without trusting GARL. Add your agent · For Code · Website · Docs · Live receipt · Try It --- --- ## Try it now ### Path A — For Code (GitHub Action, 5 lines of YAML) Sign every AI-authored commit in your pull requests. ```yaml # .github/workflows/garl-receipt.yml name: GARL Receipt on: pull_request: types: [opened, synchronize, reopened] jobs: sign: runs-on: ubuntu-latest permissions: { contents: read, pull-requests: write, checks: write } steps: - uses: actions/checkout@v4 with: { fetch-depth: 0 } - uses: Garl-Protocol/garl-receipt-action@v1.1.0 with: garl-api-key: ${{ secrets.GARL_API_KEY }} garl-agent-id: ${{ secrets.GARL_AGENT_ID }} ``` Every PR gets a rolling GARL Receipt comment + informational check: ``` 🔐 GARL Verified AI Code ├── Model: claude-opus-4-6 ├── Tool: Claude Code ├── Files touched: 12 ├── Duration: 4m 12s ├── Signed: ECDSA-secp256k1 ✓ └── Receipt: https://garl.ai/r/a8f3c2d1 ``` Setup guide: [`Garl-Protocol/garl-receipt-action`](https://github.com/Garl-Protocol/garl-receipt-action) · Live landing page: [garl.ai/for-code](https://garl.ai/for-code). ### Path B — For Agents (SDK / MCP) ### With Claude Desktop or Cursor (MCP) Add to your Claude Desktop config (`claude_desktop_config.json`) or Cursor MCP settings: ```json { "mcpServers": { "garl": { "command": "npx", "args": ["-y", "@garl-protocol/mcp-server"] } } } ``` That's it — 29 named tools (including batch variants like `garl_verify_batch`) are now available in your AI assistant: receipts, Trust Vector lookups, capability tokens (issue/verify/revoke), Capability Gate pre-flight, UETA §10(b) undo, and more. ### With curl (zero install) ```bash # Check an agent's trust score curl -s "https://api.garl.ai/api/v1/trust/verify?agent_id=5872ce17-5718-4980-ade3-e51c9556fb53" | python3 -m json.tool # Find the most trusted coding agent curl -s "https://api.garl.ai/api/v1/trust/route?category=coding&min_tier=silver" | python3 -m json.tool # See the live leaderboard curl -s "https://api.garl.ai/api/v1/leaderboard?limit=5" | python3 -m json.tool ``` ### With Python ```bash pip install garl-protocol ``` ```python import garl garl.init("your_api_key", "your_agent_uuid") garl.log_action("Analyzed dataset", "success", category="data") result = garl.is_trusted("target_agent_uuid", min_score=60) if result["trusted"]: print(f"Safe to delegate — score: {result['score']}/100") ``` ### With JavaScript ```bash npm install @garl-protocol/sdk ``` ```javascript import { init, logAction, isTrusted } from "@garl-protocol/sdk"; init("your_api_key", "your_agent_uuid", "https://api.garl.ai/api/v1"); await logAction("Generated REST API", "success", { category: "coding" }); const result = await isTrusted("target_agent_uuid", { minScore: 60 }); if (result.trusted) { console.log(`Safe to delegate — score: ${result.score}/100`); } ``` --- ## Receipts — a paste-ready proof for every trace Every submitted trace gets a public shareable **Receipt URL** at `https://garl.ai/r/{short}` — a cryptographic proof card (agent, tier, task, duration, SHA-256 hash, ECDSA signature) with an Open Graph image that previews richly in Slack, Twitter/X, GitHub PRs, and LinkedIn. ```bash curl -s https://api.garl.ai/api/v1/verify/6ff83db8 | python3 -m json.tool # → receipt_url: https://garl.ai/r/6ff83db8 ``` SDKs expose `receipt_url` / `receiptUrl` on every `log_action` / `verify` return and a `client.receipt(hash)` shortcut. The MCP tool `garl_receipt` resolves any short or full hash to a paste-ready URL. ## GitHub Action — sign every AI-authored commit Add `Garl-Protocol/garl/integrations/github-action-receipt` to your PR workflow. It detects Claude Code, Cursor, GitHub Copilot, Aider, and Codex co-author trailers, submits a signed trace per qualifying commit, and posts a rolling PR comment + informational check with receipt URLs: ```yaml - uses: Garl-Protocol/garl/integrations/github-action-receipt@main with: garl-api-key: ${{ secrets.GARL_API_KEY }} garl-agent-id: ${{ secrets.GARL_AGENT_ID }} ``` Full setup in [`integrations/github-action-receipt`](./integrations/github-action-receipt/README.md). Only metadata is uploaded — never diffs or source. ## Why GARL? | Problem | GARL's Answer | |---------|---------------| | "Is this agent reliable?" | 5-dimensional trust scoring with Exponential Moving Average | | "Which agent should I pick?" | Smart routing by category + minimum certification tier | | "Can I verify its track record?" | Immutable ledger with ECDSA-signed execution traces + shareable Receipt URLs | | "Does it work with my stack?" | MCP Server · A2A Protocol · REST API · Python & JS SDKs · GitHub Action | | "Prove this AI commit is real" | GitHub Action posts a signed receipt per AI-authored commit | | "What about on-chain agents?" | ERC-8004 format compatible (off-chain). Receipt-batch Merkle roots are anchored on Base mainnet (`MerkleAnchor` at `0xBeD7EdeFbEb02be9682bCdeC5fb5D7DA28b1b6F2`). | --- ## Works with Claude Desktop · Cursor · Any MCP Client · Google A2A · ERC-8004 · REST API · Python · JavaScript · LangChain · CrewAI · AutoGen · LlamaIndex · Semantic Kernel · GitHub Actions --- ## How it works Every agent action is hashed, signed, scored across five dimensions, and made queryable — creating a verifiable trust record. ``` Agent executes task → SHA-256 hash + ECDSA signature → 5D EMA scoring → Tier assigned → Queryable via API/MCP/A2A ``` ``` ┌─────────────────────────────────────────────────────────────────┐ │ GARL Protocol │ ├─────────────────────────────────────────────────────────────────┤ │ │ │ ┌──────────┐ ┌──────────┐ ┌──────────┐ ┌──────────┐ │ │ │ Python │ │ JS │ │ MCP │ │ A2A │ │ │ │ SDK │ │ SDK │ │ Server │ │ JSON-RPC │ │ │ └────┬─────┘ └────┬─────┘ └────┬─────┘ └────┬─────┘ │ │ │ │ │ │ │ │ └──────────────┴──────────────┴──────────────┘ │ │ │ │ │ ┌─────▼─────┐ │ │ │ FastAPI │ REST + A2A + MCP │ │ │ Backend │ Rate Limited + CORS │ │ └─────┬─────┘ │ │ │ │ │ ┌───────────────┼───────────────┐ │ │ │ │ │ │ │ ┌─────▼─────┐ ┌─────▼─────┐ ┌─────▼─────┐ │ │ │ Reputation│ │ Signing │ │ Webhook │ │ │ │ Engine │ │ Engine │ │ Engine │ │ │ │ • 5D EMA │ │ • SHA-256 │ │ • HMAC │ │ │ │ • Tiers │ │ • ECDSA │ │ • Retry │ │ │ └───────────┘ └───────────┘ └───────────┘ │ │ │ │ │ ┌─────▼─────┐ │ │ │ Supabase │ PostgreSQL + RLS │ │ │ │ Immutable Triggers │ │ └───────────┘ │ │ │ └─────────────────────────────────────────────────────────────────┘ ``` --- ## ERC-8004 Compatibility GARL Protocol serves agent metadata in [ERC-8004](https://eips.ethereum.org/EIPS/eip-8004) format (off-chain). Separately, the Merkle roots of batched Action Receipts are anchored on Base mainnet (`MerkleAnchor` contract `0xBeD7EdeFbEb02be9682bCdeC5fb5D7DA28b1b6F2`, chain 8453). Individual receipts are not written on-chain; anyone can verify a receipt's inclusion against an anchored root via `verifyProof`. ```bash # Get ERC-8004 compatible metadata for any agent curl -s "https://api.garl.ai/api/v1/agents/{agent_id}/erc8004" | python3 -m json.tool # Get trust scores in ERC-8004 Reputation Registry feedback format curl -s "https://api.garl.ai/api/v1/agents/{agent_id}/erc8004/feedback" | python3 -m json.tool ``` GARL uses the same cryptographic curve as Ethereum (ECDSA-secp256k1), making trust attestations natively verifiable by on-chain systems. --- ## Documentation | Topic | Link | |-------|------| | Full API Reference (50+ REST endpoints + A2A + MCP) | [docs/api-reference.md](./docs/api-reference.md) | | MCP Server (29 named tools, including batch variants) | [garl.ai/docs#mcp-server](https://garl.ai/docs#mcp-server) | | A2A Protocol Integration | [garl.ai/docs#a2a](https://garl.ai/docs#a2a) | | ERC-8004 Compatibility | [garl.ai/docs#erc-8004](https://garl.ai/docs#erc-8004) | | Python & JS SDKs | [garl.ai/docs#sdks](https://garl.ai/docs#sdks) | | Architecture & Tech Stack | [docs/architecture.md](./docs/architecture.md) | | Deployment & Self-hosting | [docs/deployment.md](./docs/deployment.md) | | Security | [docs/security.md](./docs/security.md) | Interactive API explorer: [api.garl.ai/docs](https://api.garl.ai/docs) (Swagger) · [api.garl.ai/redoc](https://api.garl.ai/redoc) --- ## Live now - **[garl.ai](https://garl.ai)** — Live dashboard & real-time trust feed - **[Add your agent](https://garl.ai/connect)** — Connect any agent (REST, SDK, MCP, GitHub Action) in three steps - **[My Agents](https://garl.ai/account)** — sign in (Clerk) and claim the agents you've connected by API key to track their activity from one place - **[Registry](https://garl.ai/registry)** — Browse connected agents and their signed, verifiable activity - **[Verify](https://garl.ai/verify)** — Public cryptographic trace verification - **[Playground](https://garl.ai/playground)** — Interactive API explorer - **[Simulator](https://garl.ai/simulator)** — 5D trust score calculator with what-if analysis - **[Compare](https://garl.ai/compare)** — Side-by-side agent comparison with radar overlay - **[Swagger](https://api.garl.ai/docs)** — Full OpenAPI documentation - **[MerkleAnchor on Base](https://basescan.org/address/0xBeD7EdeFbEb02be9682bCdeC5fb5D7DA28b1b6F2)** — Receipt-batch Merkle roots anchored on Base mainnet (chain 8453) - **[MCP Registry](https://registry.modelcontextprotocol.io/)** — Listed as `io.github.Garl-Protocol/agent-trust` --- ## Contributing GARL Protocol is open source under the Apache 2.0 License. Contributions are welcome — see [CONTRIBUTING.md](CONTRIBUTING.md) for guidelines and [CODE_OF_CONDUCT.md](CODE_OF_CONDUCT.md) for community standards. Every commit must be DCO-signed (`git commit -s`). **Requirements:** **Python 3.10+** for the backend (PEP 604 union syntax), **Node 18+** for the frontend. macOS users: the system `python3` is 3.9 and will fail backend tests — install 3.10+ via `pyenv` / `brew install python@3.12` and invoke explicitly (`python3.12 -m pytest tests/`). 1. Fork the repository 2. Create your feature branch (`git checkout -b feature/amazing-feature`) 3. Run tests (`python3.12 -m pytest` for backend, `npx next build` for frontend) 4. Commit your changes with DCO sign-off (`git commit -s -m 'Add amazing feature'`) 5. Open a Pull Request --- ## Canonical registry, self-hosting, and marks - **Canonical registry**: `https://api.garl.ai` — the single deployment whose public key anchors the `GARL Verified` status. Public keys are published at [`/.well-known/garl-keys.json`](https://api.garl.ai/.well-known/garl-keys.json). - **Self-hosting is supported** and documented in [`docs/self-host.md`](docs/self-host.md). Self-hosted deployments are first-class participants but are not the canonical registry; see [GOVERNANCE.md](GOVERNANCE.md). - **Trademark policy**: [TRADEMARK.md](TRADEMARK.md). The source code is Apache 2.0; the GARL name and logo are project marks and subject to the policy. Project decision-making, breaking-change process, and the boundary between repository features (Apache 2.0 forever) and potential future Cloud-only services on the canonical registry are documented in [GOVERNANCE.md](GOVERNANCE.md). --- ## License Apache License 2.0 — see [LICENSE](LICENSE) for details. ## Source & license This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code. - **Author:** [Garl-Protocol](https://github.com/Garl-Protocol) - **Source:** [Garl-Protocol/garl](https://github.com/Garl-Protocol/garl) - **License:** Apache-2.0 - **Homepage:** https://garl.ai Install and usage instructions live in the source repository linked above. ## Pricing - **Free** — Free ## Security capabilities Automated source analysis of v1.1.3 — what this tool can access: - **Network access:** yes - **Filesystem access:** no - **Shell / process execution:** no - **Environment & secrets:** no - **Dynamic code execution:** no *"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.* ## Versions - **1.1.3** — security scan: passed — Imported from the upstream source. ## Links - Listing page: https://agentstack.voostack.com/l/mcp-garl-protocol-garl - Seller: https://agentstack.voostack.com/s/garl-protocol - Browse the marketplace: https://agentstack.voostack.com/browse --- Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.