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Utility & debugging

Helper nodes for observability, validation, and ending workflows cleanly.

Log

What: Writes a message to the execution log. Visible in the per-node output and in /logs.

Inputs: Any.

Outputs: Pass-through (the input data is forwarded unchanged on output).

Configuration:

Field Notes
Message The text to log. Supports expressions.
Level debug, info, warn, error
Include input Attach the input data alongside the message

Use case: Trace what's happening between nodes during development; record audit events in production.

Example:

Message: Processed order {{ $trigger.body.orderId }} for {{ $trigger.body.customerName }} at {{ $node["Create label"].json.trackingNumber }}
Level:   info

Debug

What: Like Log but with a breakpoint-style pause. When the workflow hits a Debug node in debug mode, execution pauses until you click Continue in the editor.

Use case: Step through a workflow to inspect intermediate state.

Notes: Only takes effect when the workflow is run in debug mode (toolbar's Run dropdown → Debug). In normal runs, behaves like Log.

Terminal

What: Marks the workflow's end point and emits the final output.

Inputs: Whatever you want to return.

Outputs: The terminal output of the workflow.

Configuration:

Field Notes
Status success (default) or failed, controls the execution's final status
Output The data to return

Use case:

  • Make the final output of a workflow explicit and named (rather than implicit from the last action node).
  • Force a failed status from a logic branch without throwing an exception (e.g. "if we got this far, it's a business-rule failure").

Schema Validator Guard

What: Validates data against a JSON Schema. Routes valid items to output, invalid items to error with detailed validation messages.

Use case: Trust boundaries, validate inputs from external triggers or upstream APIs before passing them to consuming nodes.

Configuration:

Field Notes
Schema A JSON Schema object
Mode strict (any extra field is an error) or permissive (extras ignored)

Output Format Guard

What: Ensures a node's output matches an expected shape. Different from Schema Validator: the Output Format Guard reshapes / coerces, not just validates.

Operations: Drop unexpected fields, coerce types, fill missing fields with defaults.

Use case: Normalising AI Agent output that's supposed to be JSON but sometimes isn't quite.

Rate Limiter Guard

What: Throttles a downstream operation to N invocations per time window.

Configuration:

Field Notes
Max calls e.g. 100
Window e.g. 60 seconds
Behaviour on limit block (delay until budget refills), drop (skip), error

Use case: Protecting yourself from accidentally overwhelming a flaky downstream API even when retries kick in.

Set

Covered in Storage & database. Reproduced here for discoverability because it's heavily used for debugging, set a checkpoint value, use the inspector to see what's in it, decide what to do next.

Cache Storage

Covered in Storage & database. Useful in debugging for caching slow upstream calls during iteration.

Tips & gotchas

  • Log everything during development; trim before production. Verbose logs cost storage and obscure the real signal.
  • The Debug node is editor-only. In production runs scheduled or webhook-triggered, it logs but doesn't pause.
  • Schema Validator Guard's error messages are JSON Schema-style, readable but not always user-friendly. Wrap with a Data Transform if you need to surface them to humans.
  • Rate Limiter is per-worker, per-key. In a multi-worker deployment, two workers each get their own budget unless you switch the backend to Redis (admin-configured).

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