Connect Your Agent to n8n Workflows

n8n is a visual workflow automation platform used for multi-step automations across APIs, databases, and internal tools. The n8n Workflow Connector lets your AgentPMT agent list your n8n workflows, trigger them with structured data and file attachments, and ingest their output — all from a conversation.

By the end of this tutorial, you will have an active n8n workflow that your AgentPMT agent triggers with structured data, attaches files to, and reads results back from. You will also know how to monitor execution status and ingest any files the workflow produces.

What You Will Need#

• An AgentPMT account with a connected agent — follow Sign Up And Connect Your Agent if you have not yet
• An n8n account — either a paid n8n Cloud plan or a self-hosted instance with a public URL
• About 15 minutes

Step 1 — Getting Your n8n API Key#

An n8n API key lets your AgentPMT agent authenticate REST API calls to your instance — listing workflows, reading execution history, and fetching workflow details. n8n issues API keys from its built-in settings UI with configurable expiration. Webhook triggering uses a separate URL with its own optional auth, so the API key alone is sufficient for most setups.

Step 2 — Finding Your n8n Instance URL#

Your instance URL is the base address of your n8n dashboard — the root of every API call and webhook URL your agent will make. n8n Cloud assigns one automatically when you sign up. Self-hosted instances need a publicly reachable domain configured via the WEBHOOK_URL environment variable so that outbound webhook URLs resolve correctly from the public internet.

Step 3 — Connecting n8n in AgentPMT#

AgentPMT injects your n8n credentials automatically at runtime so you never paste the API key into a chat. The platform encrypts both the API key and instance URL at rest and binds them to your budget and product. When your agent calls any connector action, AgentPMT pulls the credentials securely and signs the request — no further user action needed.

Step 4 — Making Your Workflow Triggerable#

n8n workflows can only be triggered externally through Webhook nodes — the public n8n REST API has no execute workflow by ID endpoint. Adding a Webhook node as the first trigger gives the workflow a URL your agent can call. The node configuration controls the HTTP method, the path slug, and whether the HTTP response waits for the workflow to finish or returns immediately.

Step 5 — Triggering Your Workflow#

With a triggerable workflow active and credentials connected, your agent can list your workflows, discover webhook paths, and fire off a trigger call with structured data. The three-call flow — list_workflows, get_workflow, trigger_workflow — is the standard interaction pattern, and the connector auto-discovers webhook paths from the workflow definition so you never need to hand-copy URLs.

Show me my n8n workflows

{
  "action": "list_workflows",
  "workflows": [
    {
      "id": "h7SSBY2GM4fo9mqG",
      "name": "process-order",
      "active": true,
      "tags": []
    }
  ],
  "count": 1,
  "next_cursor": null
}

Get the details for workflow h7SSBY2GM4fo9mqG

{
  "action": "get_workflow",
  "id": "h7SSBY2GM4fo9mqG",
  "name": "process-order",
  "active": true,
  "webhook_triggers": [
    {
      "node_name": "Webhook",
      "path": "process-order",
      "method": "POST",
      "response_mode": "lastNode"
    }
  ],
  "webhook_urls": [
    "https://yourname.app.n8n.cloud/webhook/process-order"
  ]
}

Trigger my process-order workflow with order_id "12345" and customer_email "user@example.com"

{
  "action": "trigger_workflow",
  "webhook_url": "https://yourname.app.n8n.cloud/webhook/process-order",
  "status_code": 200,
  "response": {
    "status": "processed",
    "order_id": "12345",
    "confirmation_sent": true
  }
}

Step 6 — Attaching Files From the File Manager#

Your AgentPMT File Manager stores documents, images, and datasets your agent has generated or received. When triggering an n8n workflow, the connector can attach any File Manager file as a signed download URL embedded in the webhook payload under _agentpmt_files. The n8n workflow fetches the content via an HTTP Request node — keeping large files out of the webhook body itself.

Trigger my process-order workflow with order_id "12345" and attach file f7d2f9d5-2d45-4d41-9d84-0dd5f6de1234

{
  "order_id": "12345",
  "_agentpmt_files": [
    {
      "file_id": "f7d2f9d5-2d45-4d41-9d84-0dd5f6de1234",
      "filename": "customer-order.pdf",
      "content_type": "application/pdf",
      "size_bytes": 48291,
      "download_url": "https://storage.googleapis.com/...",
      "expires_in_minutes": 60
    }
  ]
}

Step 7 — Ingesting Output Files Into the File Manager#

When an n8n workflow produces file URLs in its output — generated reports, exported datasets, rendered images — your agent can automatically ingest them into the AgentPMT File Manager. The connector scans the execution output for downloadable URLs, pulls the content, and uploads it with a new file_id your agent can reference in follow-up tool calls.

Get execution 456 and save any output files to my File Manager

{
  "action": "get_execution",
  "id": "456",
  "status": "success",
  "output": [
    {
      "report_url": "https://example.com/reports/q1-2026.pdf"
    }
  ],
  "ingested_files": [
    {
      "source_url": "https://example.com/reports/q1-2026.pdf",
      "file_id": "b94c8f2a-17de-4fa8-b3b8-2c9e0f1a5b42",
      "filename": "q1-2026.pdf",
      "size_bytes": 204819,
      "signed_url": "https://storage.googleapis.com/..."
    }
  ]
}

What is the difference between sync and async n8n workflows?#

The difference is whether your agent waits for the n8n workflow to finish before continuing. Sync mode — Webhook response mode When Last Node Finishes — keeps the HTTP connection open and returns the workflow output directly, best for workflows under 60 seconds. Async mode — response mode Immediately — returns a 200 acknowledgment instantly while the workflow runs in the background; your agent polls list_executions or get_execution to retrieve results when the workflow finishes.

Troubleshooting#

Frequently Asked Questions#

Does this work with self-hosted n8n Community Edition?#

Yes. The n8n public REST API and webhook system are available on all editions, including the free self-hosted Community Edition. The only requirement is that your instance is publicly reachable from the internet. Localhost-only installations or instances behind a firewall without inbound rules cannot be contacted from AgentPMT.

Do I need a paid n8n Cloud plan to use this connector?#

Yes, for n8n Cloud users. The n8n public API is not available during the free trial on n8n Cloud — you need a Starter plan or higher for API key creation. Self-hosted Community Edition users have full API access for free.

Can I trigger workflows that do not have a Webhook node?#

No. n8n's public REST API has no endpoint to execute an arbitrary workflow by ID — Webhook nodes are the only supported external trigger. Any workflow you want your agent to trigger must have a Webhook as its first node. Existing cron-triggered or event-triggered workflows can be duplicated with a Webhook trigger added if needed.

What happens if my workflow takes longer than 60 seconds?#

Increase webhook_timeout in the trigger call up to 300 seconds, or switch the Webhook node's response mode to Immediately for async mode. In async mode, your agent gets an instant 200 and then polls get_execution or list_executions to retrieve results when the workflow finishes.

Are my n8n credentials stored securely?#

Yes. AgentPMT encrypts both your API key and instance URL at rest and injects them at runtime, scoped to your budget and product. Your agent never sees the raw credentials in a chat. See How Credentials Work for the full security model.

Can I connect more than one n8n instance?#

Each n8n Workflow Connector instance binds one API key and one instance URL. To use multiple n8n instances — for example, staging and production — add the connector as separate tool connections, each with its own credentials.

Related Docs#