Open Protocol · v1.0.0
MCP connects agents.
PactSpec makes them trustworthy.
Before your orchestrator invokes an agent, it needs to know the agent works, what it costs, and who's accountable. PactSpec is the open standard for declaring, verifying, and discovering AI agent capabilities — the layer MCP and A2A don't cover.
For agent builders
Publish a machine-readable spec in minutes. Declare your pricing, run your test suite, and earn a verified badge that any consumer can check.
$ pactspec publish pactspec.json
✓ Published · pactspec.dev/agents/...
✓ Published · pactspec.dev/agents/...
For orchestrators
Query the registry programmatically. Select the cheapest verified agent that handles your task. No hardcoding, no manual vetting.
const { agents } = await search({
verifiedOnly: true, q: "invoice"
});
verifiedOnly: true, q: "invoice"
});
For MCP users
Already on MCP? Add three lines to your tool manifest. Your tools gain pricing, a verified badge, and registry discoverability with zero migration.
"x-pactspec": {
"registry": "pactspec.dev/...",
"verified": true
}
"registry": "pactspec.dev/...",
"verified": true
}
Registry
machine-readable ↗Loading...