Add fact-checking to any n8n workflow.

The Lenz node is available on n8n.io. Drop it into any workflow — after an AI content step, before a send, wherever a false claim would cause a problem — and get a sourced verdict, score, and citations back as structured JSON. No HTTP configuration. Just your API key.

What you can do with the node

Any workflow that generates or processes content has a natural insertion point for verification.

• Screen AI-written content before it publishes — route by verdict to approve, revise, or escalate to a human.
• Verify claims extracted from documents or web content before they feed downstream systems or summaries.
• Add a sourced verdict step to a content QA pipeline: verdict, score, and source URLs arrive as structured fields, ready to branch on.
• Route low-confidence results to a human review queue, then continue automatically once they clear.

What the node returns

The node has five operations. Each returns its own structured JSON shape, and every field is machine-readable and wires directly to downstream nodes.

{
  "status":            "completed",     // completed | needs_input | timeout | failed
  "passed":            true,            // true for True and Mostly True
  "verdict":           "Mostly True",   // True | Mostly True | Mixed | Mostly False | False
  "lenz_score":        7,               // integer 1–10
  "confidence":        "high",         // how much the panel agreed
  "key_finding":       "...",          // one sentence — the short form for Slack/email
  "executive_summary": "...",          // the longer write-up
  "citations":         [...],           // sources, each with title and url
  "verification_id":   "a1b2c3d4"      // look the check up later via the API
}

On Verify (Deep), branch on status — only completed carries a verdict; needs_input, timeout and failed need their own path. Then passed is the ready-made boolean for approve/escalate, with verdict and lenz_score if you want a finer threshold. citations is an array of source objects, each with a title and a url. Keep verification_id if you want to pull the full reasoning trace from the API later — the node doesn't carry it inline, and Ask Follow-Up needs it.

Verify (Deep) runs synchronously and polls for up to two minutes before returning status: "timeout", so a workflow on that operation can block for that long. Assess (Fast) returns in seconds — use it for bulk screening and reserve Verify for the claims that warrant it.

Getting started

Three steps from zero to a working fact-check node.

1. Get a free API key → — no credit card required.
2. Open n8n, search for Lenz in the node panel, and drag it into your workflow.
3. Add your lenz_… API key under Credentials → Lenz API. Wire input and output. Done.

The node is available from the n8n community nodes registry — no manual install. View the Lenz node on n8n.io ↗

Resources

Add fact-checking to your n8n workflow.

Self-serve from day one. Free tier, no card required.