langchain-aotrust

LangChain tools for AOTrust notarization — cryptographic proof-of-existence for AI agent outputs. Free tier (no wallet required), PDRs signed with Ed25519, Merkle-included and anchored on NEAR.

Works with any agent built on langchain-core (LangChain, LangGraph, CrewAI via the standard BaseTool interface, pydantic-ai adapters).

Install

pip install langchain-aotrust

Quickstart

from langchain_aotrust import (
    aotrust_notarize_free,
    aotrust_verify,
    aotrust_status,
)

# 1. Notarize an artifact (free tier — no API key, no wallet)
print(aotrust_notarize_free.invoke({"artifact_text": "analysis v3: portfolio risk moderate"}))
# Notarized (tier=free). shield_id=9f2c... job_id=7a1b... work_hash=...
# Verify later at https://verify.aotrust.link or with aotrust_verify(job_id).

# 2. Check pipeline status
print(aotrust_status.invoke({"job_id": "<job_id>"}))
# Status for job_id=7a1b...: status=anchored, anchored=yes, payment_hash=...

# 3. Full cryptographic verification
print(aotrust_verify.invoke({"job_id": "<job_id>"}))
# Verification for job_id=7a1b...: valid=True, payment_anchor_type=0, ...

Wiring into a LangChain agent:

from langchain_aotrust import aotrust_notarize_free, aotrust_verify
from langchain.agents import create_tool_calling_agent  # any agent works

tools = [aotrust_notarize_free, aotrust_verify, aotrust_status]

Async agents (LangGraph) can await the plain functions directly:

from langchain_aotrust import aotrust_notarize_free_async
result = await aotrust_notarize_free_async(artifact_text="...")

Configuration (optional — defaults to the public endpoint):

from langchain_aotrust import configure
configure(base_url="https://api.aotrust.link")  # NO /v1 suffix — the SDK appends paths

What the proofs mean

Free tier

• No API key, no wallet, no payment.
• Rate limited per IP (5 notarizations / 24h) — paid x402 tier ($0.01) in a future release for higher throughput.

Links

• Docs: https://docs.aotrust.link
• Live verifier: https://verify.aotrust.link
• SDK: https://pypi.org/project/aotrust-protocol/

License

MIT