LangChain

beav3r-sdk-langchain lets LangChain tools route through Beav3r before execution.

Use it when tool calls must be approved, denied, or blocked by policy before the handler runs.

Install


python3 -m pip install beav3r-sdk beav3r-sdk-langchain langchain-openai

Required environment

For the included example script (examples/simple_agent.py):

BEAV3R_BASE_URL
BEAV3R_API_KEY
OPENAI_API_KEY
optional OPENAI_BASE_URL (defaults to https://api.openai.com/v1)
optional MODEL_NAME (defaults to gpt-4.1-mini)
optional BEAV3R_TIMEOUT_MS

Example middleware wiring


from beav3r_sdk import Beav3r
from langchain.agents import create_agent
from langchain_openai import ChatOpenAI
from langchain_beav3r import Beav3rApprovalMiddleware, Beav3rToolConfig
 
 
def send_usdt(amount: int, recipient: str) -> str:
    return f"Sent {amount} USDT to {recipient}"
 
 
client = Beav3r(
    base_url=base_url,
    api_key=api_key,
    agent_id="langchain_demo",
)
 
model = ChatOpenAI(
    model=model_name,
    api_key=provider_api_key,
    base_url=provider_base_url,
    temperature=0,
)
 
agent = create_agent(
    model=model,
    tools=[send_usdt],
    middleware=[
        Beav3rApprovalMiddleware(
            client,
            tool_configs={
                "send_usdt": Beav3rToolConfig(action_type="payments.send_usdt"),
            },
            timeout_ms=timeout_ms,
        )
    ],
)

This matches examples/simple_agent.py in beav3r-sdk-langchain.

Run the example


export BEAV3R_BASE_URL=https://staging.server.beav3r.ai
export BEAV3R_API_KEY=bvr_test_...
export OPENAI_API_KEY=...
# optional
# export OPENAI_BASE_URL=https://api.openai.com/v1
# export MODEL_NAME=gpt-4.1-mini
# export BEAV3R_TIMEOUT_MS=300000
 
python3 examples/simple_agent.py

Runtime outcomes

approved or executed: tool runs
denied, rejected, or expired: tool is blocked
still pending: Beav3rApprovalPendingError is raised

Docker path


bash scripts/run_simple_agent_docker.sh

The Docker script installs sibling beav3r-sdk-py, installs this adapter, and runs the same example.