Prompt Engineering Data Extraction Structured Output

Extract Data From Text with AI

Free text in, named fields out. The extraction prompt pattern that turns any unstructured text into consistent, parseable records.

Overview

Asking a model to "pull out the important information" produces different fields every run. Reliable extraction means naming the fields, describing what each one holds, and deciding two things up front: what happens when a value is missing, and how much inference is allowed. This resource loads a lead-form extraction — free text from a contact form into six named CRM fields, strict ambiguity, null for anything absent — the smallest complete example of the pattern that works on any text.

Workflow

  1. Name the fields, not the wish

    Replace "important details" with lead_name, email, use_case — fields the consumer can rely on existing.

  2. Decide the missing-data behavior

    Null keeps keys stable for pipelines; empty or "unknown" keeps gaps visible for humans. Decide once, in the prompt.

  3. Set the ambiguity policy

    Strict for data you'll act on, best guess for data you'll review. The default drift between the two is where inconsistency comes from.

Why This Works

  • Named fields with descriptions turn a vague request into a checkable contract
  • Explicit missing-data rules eliminate the model's biggest improvisation point
  • The example extraction shows the exact shape, so the model imitates instead of inventing

Best for

  • Any pipeline that feeds model output into code or a spreadsheet
  • Teams tired of extraction results that change shape between runs
  • Texts with no fixed layout — notes, messages, form dumps

Not for

  • Defining the output format in depth — that's the JSON Output Prompt Builder
  • Assigning labels from a fixed set — that's classification, not extraction

Use cases

  • Turning free-text form submissions into CRM-ready records
  • Getting the same six fields out of every text, every run
  • Replacing "summarize the key info" prompts with named-field extraction

Tip: Save time by exploring related resources and tools that integrate with this workflow.

Explore all resources