#!/usr/bin/env python3
"""
Minimal, no‑LLM MCP client that calls tools directly over HTTP JSON‑RPC.
Usage:
VAULT_MCP_BASE_URL=http://127.0.0.1:8089 \
VAULT_MCP_API_KEY=dev-api-key \
python -m examples.langchain_agent.agent_no_llm --path configs/no_llm --data '{"foo":"bar"}'
Or with bearer token:
VAULT_MCP_BEARER_TOKEN=... python -m examples.langchain_agent.agent_no_llm --path configs/no_llm
"""
import os
import json
import argparse
import httpx
def _headers() -> dict:
h = {"Content-Type": "application/json"}
api = os.environ.get("VAULT_MCP_API_KEY")
tok = os.environ.get("VAULT_MCP_BEARER_TOKEN")
if api:
h["X-API-Key"] = api
if tok:
h["Authorization"] = f"Bearer {tok}"
return h
def rpc(client: httpx.Client, base: str, body: dict) -> dict:
r = client.post(base.rstrip("/") + "/mcp/rpc", json=body, headers=_headers(), timeout=10.0)
r.raise_for_status()
js = r.json()
if "error" in js:
raise RuntimeError(js["error"])
return js.get("result") or {}
def main():
ap = argparse.ArgumentParser()
ap.add_argument("--base", default=os.environ.get("VAULT_MCP_BASE_URL", "http://127.0.0.1:8089"))
ap.add_argument("--path", default="configs/no_llm")
ap.add_argument("--data", default='{"foo":"bar"}', help="JSON string for write")
args = ap.parse_args()
data_obj = json.loads(args.data)
with httpx.Client() as client:
print("[no-llm] initialize")
print(rpc(client, args.base, {"jsonrpc": "2.0", "id": 1, "method": "initialize"}))
print("[no-llm] tools/list")
tools = rpc(client, args.base, {"jsonrpc": "2.0", "id": 2, "method": "tools/list"})
print([t.get("name") for t in tools.get("tools", [])])
print(f"[no-llm] kv.write {args.path}")
wr = rpc(
client,
args.base,
{"jsonrpc": "2.0", "id": "w1", "method": "tools/call", "params": {"name": "kv.write", "arguments": {"path": args.path, "data": data_obj}}},
)
print(wr)
print(f"[no-llm] kv.read {args.path}")
rd = rpc(
client,
args.base,
{"jsonrpc": "2.0", "id": "r1", "method": "tools/call", "params": {"name": "kv.read", "arguments": {"path": args.path}}},
)
print(rd)
if __name__ == "__main__":
main()
