vouch-langgraph

Sign every LangGraph tool call and graph node with a Vouch Credential, so an agent's actions carry a verifiable record of who ran them and on whose authority.

LangGraph tools are LangChain tools, so tool-level signing is shared with the LangChain integration. On top of that, sign_node signs each node step, giving a signed trail across the whole graph.

Install

pip install vouch-langgraph

Sign the tools

from langgraph.prebuilt import create_react_agent
from vouch.integrations.langgraph import protect

agent = create_react_agent(llm, tools=protect([search, send_email]))

Every tool call is now signed in Python before it runs.

Sign each node

from vouch.integrations.langgraph import sign_node

@sign_node
def plan(state):
    ...

@sign_node(action="charge_card")
def bill(state):
    ...

Each node step issues its own credential. Verify anywhere with vouch.Verifier.verify_credential, or read the latest with vouch.autosign.current_credential.

Identity

protect and sign_node use the ambient Vouch identity, or a signer= you pass in. Provision one with vouch init --yes, or construct a Signer directly. See the Vouch Protocol docs.

License

Apache-2.0. Part of the Vouch Protocol.