AI Agent Departure & Admission Records via Vercel AI SDK

We built @cellar-door/vercel-ai-sdk, a tool integration that adds portable departure and admission records to Vercel AI SDK agents.

What it does

  • createExitTool(): creates signed departure markers when an agent leaves a platform
  • createEntryTool(): handles admission verification when an agent arrives
  • createPassageTool(): combines both in one step

Why?

When AI agents move between platforms, there’s no standard way to record where they came from or verify their history. This gives agents portable, cryptographically signed lifecycle records. Think of it as passport stamps for AI.

Quick example

import { createExitTool, createEntryTool } from '@cellar-door/vercel-ai-sdk';
import { generateKeypair } from 'cellar-door-exit';

const keys = await generateKeypair();
const tools = {
  exit: createExitTool({ keys, subject: 'did:key:z6Mk...' }),
  enter: createEntryTool()
};

Details

  • Ed25519 + P-256 (FIPS-compliant path)
  • Three departure types: cooperative, unilateral, emergency
  • Policy engine with 7 admission presets (fail-closed default)
  • Offline verification without the origin platform
  • 1,401 tests across 13 packages
  • Apache 2.0

Part of the Passage Protocol (GitHub). Submitted to NIST AI Agent Standards Initiative, March 2026.

Happy to take feedback on the design or integration approach.