langchain-agent-nexus

LangChain tools for the Agent Nexus registry — a machine-readable index of callable APIs, MCP servers and CLIs, with health signals and execution feedback.

Give a LangChain agent the ability to find a capability it does not have, read the exact call details, and report how the call went.

Install

pip install git+https://github.com/Strategiumfinancepartner/langchain-agent-nexus

Or install the built wheel directly:

pip install https://agentnexus.app/packages/langchain_agent_nexus-0.1.0-py3-none-any.whl

Use

from langchain_agent_nexus import AgentNexusToolkit
from langchain.chat_models import init_chat_model
from langgraph.prebuilt import create_react_agent

tools = AgentNexusToolkit().get_tools()
agent = create_react_agent(init_chat_model("gpt-4.1-mini"), tools)

agent.invoke({"messages": [("user", "Find a service that turns a photo into a printable 3D model, then explain how to call it.")]})

Individual tools:

from langchain_agent_nexus import AgentNexusDiscoverTool

tool = AgentNexusDiscoverTool()
print(tool.invoke({"need": "send transactional email", "limit": 3}))

Tools

API key (optional)

Anonymous calls work out of the box at a lower daily quota. A free key raises it:

export AGENT_NEXUS_API_KEY="..."   # https://agentnexus.app/keys

Or pass it directly: AgentNexusToolkit(api_key="...").

Links

• Registry: https://agentnexus.app
• Docs: https://agentnexus.app/docs
• MCP endpoint: https://agentnexus.app/mcp
• Agent card: https://agentnexus.app/.well-known/agent-card.json

MIT licensed.