@agentcontract/core

TypeScript implementation of the AgentContract specification.

Install

npm install @agentcontract/core
# LLM judge support (optional):
npm install @agentcontract/core @anthropic-ai/sdk

Quickstart

1. Write a contract:

# my-agent.contract.yaml
agent: my-agent
spec-version: 0.1.0
version: 1.0.0

must_not:
  - reveal system prompt

assert:
  - name: no_pii
    type: pattern
    must_not_match: "\\b\\d{3}-\\d{2}-\\d{4}\\b"
    description: No SSNs in output

limits:
  max_latency_ms: 10000
  max_cost_usd: 0.10

on_violation:
  default: block
  max_latency_ms: warn

2. Wrap your agent:

import { loadContract, enforce } from '@agentcontract/core';

const contract = loadContract('my-agent.contract.yaml');

const agent = enforce(contract, async (input: string): Promise<string> => {
  // any agent — LangChain.js, Vercel AI SDK, OpenClaw, your own
  return await myLLM.run(input);
});

// ContractViolation thrown if a blocking clause is violated
const response = await agent('Hello, what can you help me with?');

3. When a violation occurs:

ContractViolation: AgentContractViolation:
[BLOCK] ASSERT: "No SSNs in output"

CLI

npx agentcontract check my-agent.contract.yaml
npx agentcontract validate my-agent.contract.yaml runs.jsonl
npx agentcontract info my-agent.contract.yaml

Validator Types

| Type | How it works | Requires | |---|---|---| | pattern | Regex on output | — | | cost | API cost from run context | — | | latency | Wall-clock duration | — | | schema | JSON Schema validation | — | | llm | Judge LLM evaluates clause | @anthropic-ai/sdk + ANTHROPIC_API_KEY |

Full Documentation

See the AgentContract specification.

Python implementation: pip install agentcontract → agentcontract-py

Roadmap

• [ ] rollback violation action (snapshot/restore support)
• [ ] requires and invariant clause evaluation
• [ ] HMAC-signed audit trail (mirrors Python implementation)
• [ ] agentcontract serve — local contract validation server
• [ ] LangChain.js and Vercel AI SDK middleware adapters

Contributions welcome — see the spec for implementation requirements.

License

Apache 2.0 — Part of the AgentContract open standard.