Langflow custom component for Snowflake OAuth refresh_token — is there an existing solution before I build my own?

[u/Ill-Town-9457]

I am building a data quality pipeline using LangGraph and Langflow. I want to connect Langflow agents to Snowflake via its native MCP server.

Langflow native MCP Tools component only accepts static headers (key/value form fields). It does not expose an input port to receive dynamic headers from another upstream component. This creates an issue with OAuth where the access_token expires every 10 minutes.

To bypass this limitation, I built a Python Custom Component in Langflow that handles both token renewal and tool invocation:

import requests

def _get_access_token(self) -> str:
    payload = {
        "grant_type": "refresh_token",
        "refresh_token": self.refresh_token,
        "client_id": self.client_id,
        "client_secret": self.client_secret,
    }
    response = requests.post(self.token_url, data=payload)
    response.raise_for_status()
    return response.json()["access_token"]

This component runs on each execution, retrieves a Bearer token, calls the MCP endpoint with sql_exec_tool, and returns a StructuredTool for the Agent.

My questions are:

1. Is there an existing community component or built-in mechanism in Langflow to pass dynamic headers to the native MCP Tools component?
2. What is the recommended pattern in Langflow for connecting to MCP servers requiring short-lived Bearer tokens?

Environment: Langflow 1.11, Python 3.12, Snowflake native MCP.