n8n Workflow: Check & Route x402 Payments via OpenAI + MCP

Check and route x402 (pay-per-call USDC) endpoints automatically—using OpenAI + Settled MCP

This n8n workflow reads an x402 endpoint request from your n8n chat, evaluates the endpoint using OpenAI decision rules, and then verifies delivery/payability signals via Settled’s MCP tools to produce a single, actionable pay/avoid/alternative decision.

What this workflow does

• Triggers from n8n chat: when a message includes an x402 endpoint URL or asks to find endpoints for a job.
• Interprets the request with OpenAI: an OpenAI chat model interprets the user intent and applies the workflow’s built-in decision rules for evaluating x402 endpoints.
• Verifies status with Settled MCP: it calls Settled’s MCP tools (for example, settled_check, and when needed settled_submit) to validate endpoint status, quote details, and delivery/payability signals based on Settled’s signed on-chain observations.
• Decides in one line: if the endpoint is risky, dead/unknown, or has mismatched payment details, it responds with a one-line decision citing the deciding Settled field and avoids payment.
• Proceeds when payability thresholds are met: if the endpoint is free, verified delivered, or meets payability and quality thresholds, it responds with a one-line decision citing the deciding Settled field and proceeds with the recommended action.
• Offers options when you ask: when given a job description instead of a specific URL, it can use tools like settled_find_endpoints (and settled_income_venues) to return relevant endpoints or venues.

Use cases

• SaaS operators automating pay-per-call (x402 USDC) routing decisions from chat requests.
• Automation engineers building an n8n pipeline that avoids risky or mismatched x402 payment endpoints.
• Teams needing endpoint discovery for a job, returning candidate endpoints/venues for evaluation.

Technical details

• n8nnodes: n8nn8n-nodes-langchainchat trigger, n8nn8n-nodes-langchainlm chat open ai, n8nn8n-nodes-langchainmcp client tool, n8nn8n-nodes-langchainagent, plus a sticky note.
• OpenAI integration: configure an OpenAI API credential in the OpenAI Chat Model node (or swap for another compatible chat model node).
• Settled MCP: workflow reaches https://settled.tools/mcp/free (no authentication).