Webhook requests sorted into four routes by Claude

Webhook requests sorted into four routes by Claude

An n8n workflow with a webhook. You post any request to it, and Claude Haiku 4.5 labels the request support, technical,
sales or general, with a priority and a one-sentence summary. The caller gets that label back in the same call, and a
Switch node splits the request across four outputs for nodes of your own.

What is inside

• workflow.json: the workflow as n8n exports it, five nodes and no sticky notes. It holds no credential.
• README.md: these notes.

What we changed from the original copy

• Route Switch had fallbackOutput set to extra outside its options, where n8n ignores it, so a request labeled
  general had no output. The setting now sits in options, and the node shows a fourth output.
• Claude Classifier put JSON.stringify($json.body || $json) between quote marks inside its JSON body. The payload's
  own quote marks ended the string early, so any real request broke the body. The text now goes through a second
  JSON.stringify, which adds the outer quotes and escapes the inner ones.
• Return Route Result put Claude's summary between quote marks the same way. It now uses JSON.stringify, so a
  quote mark in the summary no longer breaks the reply.
• The webhook's webhookId and the file's template ids are gone. Nothing else changed: the model, the API version and
  the wiring are the file's own. We checked the two body repairs by filling the templates in a script, and have not run
  them in a live n8n.

Before you start

• An n8n instance, on n8n Cloud or your own server.
• An Anthropic API key for the Messages API, with access to claude-haiku-4-5.
• A way to send a POST with a JSON body, such as curl or a form.

Set it up

1. In n8n, create a workflow, open its menu and choose Import from File. Pick workflow.json.
2. Give your n8n server an environment variable named ANTHROPIC_API_KEY with your key. The x-api-key header in
   Claude Classifier reads it as $env.ANTHROPIC_API_KEY. Where you cannot set server variables, type your key over
   that expression instead. n8n can also block variable access in expressions: its security settings page lists
   N8N_BLOCK_ENV_ACCESS_IN_NODE, which is false by default.
3. Open Incoming Webhook and copy its test address. The path is ai-router.
4. Save, press Execute workflow and post a JSON body to the test address, such as a message and a name.
5. Read the reply, then attach your own nodes to the outputs of Route Switch.
6. Press Publish and post to the production address.

How a run goes

1. Incoming Webhook (Webhook 2) listens for a POST at ai-router and holds the answer until Return Route Result
   replies.
2. Claude Classifier posts to https://api.anthropic.com/v1/messages with anthropic-version 2023-06-01,
   claude-haiku-4-5 and max_tokens 100. Its system message tells Claude to answer only with a JSON object that
   holds the route, the priority and a summary, and to pick the route from support, sales, technical and general.
3. Parse Classification reads the first text block, takes the first {...} from it and parses it. When that fails it
   uses route general, priority medium and summary Unable to classify. It keeps the webhook's item as
   originalPayload.
4. Route Switch (Switch 3) compares route with support, technical and sales, ignoring case. The fourth output
   takes everything else.
5. Return Route Result (Respond to Webhook) answers with JSON: received, route, priority and summary.

The webhook feeds two lines: Claude Classifier above and Return Route Result below. The file's execution order is
v1, which runs the upper line to its end before the lower one, so the reply can read what Parse Classification
found. Keep the reply node below the classifier on the canvas.

Change the look

• Routes: the list in the system message of Claude Classifier, and the three rules in Route Switch. Keep them in
  step. A new route needs a new rule and a new output.
• Model: model in the JSON body of Claude Classifier.
• Length: max_tokens there. 100 is enough for a route, a priority and one sentence.
• Reply: the JSON in Return Route Result.
• What happens next: attach nodes to the outputs of Route Switch, such as a Slack message for support or a CRM row for
  sales. Each one receives the route, the priority, the summary and originalPayload.

Good to know

• The four outputs of Route Switch have nothing attached. The workflow labels and replies, and the request stops at
  the Switch until you add your own nodes.
• Anthropic's deprecations page, read on 12 November 2026, lists claude-haiku-4-5-20251001 as active, with no
  shutdown date announced.
• Each request is one Messages API call, with at most 100 tokens in the answer.
• Once the workflow is published, anyone who knows the address can post to it and spend your key. Add authentication
  in Incoming Webhook before you share it.
• The whole request body goes to Anthropic. Keep out anything you do not want a model to read.
• The file holds no credential and no key. It reads yours from a server variable.