Engineering YAML Structured Output

YAML Output Prompts

When the consumer is a config file or a human-reviewed pipeline, YAML beats JSON. The same output-contract engine, rendered as a YAML mode.

Overview

YAML output makes sense in a narrow band: configuration files, CI pipelines, and outputs a human reviews before committing. The contract mechanics are identical to JSON — schema, example, validation, strictness — with YAML-specific rules taking over: two-space indentation, quoting for special characters, no document separators. This resource loads an event-registration contract in YAML mode to show the engine's format switch in action; if your consumer is code rather than a file, the same schema is one click away from JSON.

Workflow

  1. Generate in YAML mode

    Same schema engine, YAML serializer — note the format-specific rule block.

  2. Check the indentation rule

    Two-space indentation is pinned explicitly; indentation drift is YAML's signature failure.

  3. Flip formats to compare

    Switch the select to JSON and watch the contract re-render — the schema investment is format-portable.

Why This Works

  • Format-specific rules address each format's own failure modes — YAML's is indentation, not fences
  • One engine across formats means the schema is defined once and rendered anywhere
  • Choosing the format by consumer (file vs parser) is the decision the mode select encodes

Best for

  • DevOps and CI workflows where YAML is the native tongue
  • Outputs destined for files rather than parsers
  • Teams that already settled the JSON-vs-YAML question per consumer

Not for

  • Code consumers — JSON parses more predictably; switch the format select back
  • Deeply nested structures where YAML indentation errors get expensive

Use cases

  • Generating config-file entries a human reviews before commit
  • Producing pipeline definitions in YAML-native ecosystems
  • Switching an existing JSON contract to YAML without redesigning it

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

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