Use this when
An AI pulls values from unstructured input, an email, a document, a form, and the workflow will act on those values.
The pattern
UNSTRUCTURED INPUT
↓
AI EXTRACTS values into fields
↓
RULES VALIDATE each field (format, range, match)
↓
VALID? ── Yes → workflow proceeds
└─ No → send to a person
The AI does the interpreting; deterministic rules check its work before anything depends on it.
Why it works
Extraction is interpretation, so it can be wrong, and a wrong value often looks clean and confident. Validation catches many of those errors cheaply: a total that is not a number, a date in the past, an order reference that matches no real order. It puts a deterministic guard between a probabilistic step and a real action.
This is the practical way to turn unstructured data into something the rest of the workflow can trust.
How to apply it
- Define the fields to extract and their expected form.
- For each field, write validation rules: format, range, and matches against known records.
- Let valid results flow on; send anything that fails to a person.
- Watch which fields fail most often; that points to input or extraction problems worth fixing.
Good fit
- Invoices, forms, delivery notes, orders, any document-to-fields task.
- Anywhere extracted values feed a consequential step.
Poor fit
- Fields that cannot be meaningfully validated, where you must rely on review instead.
What this does not solve
Validation catches many extraction errors, not all of them. A plausible, well-formed, wrong value can pass. Combine it with a confidence threshold and, for consequential cases, human review.


