---
title: "Read one DecisionCase in ten minutes."
description: "Follow how options, assumptions, dissent, scenarios, and review conditions stay bound to evidence lineage in a fixed example."
updated: "30 August 2026"
availability: "CONTRACT REVIEW · TEST_ONLY"
candidate_route: "/docs/polya/getting-started"
---

# Read one DecisionCase in ten minutes.

Follow how options, assumptions, dissent, scenarios, and review conditions stay bound to evidence lineage in a fixed example.

**CONTRACT REVIEW · TEST_ONLY:** Review-candidate contract and local fixture evidence only · no distributed SDK, operational API, publisher parity, or decision authority

## This is a contract review, not an installation flow

The current PÓLYA documentation covers the `@polya/contract-ontology@1.0.0-review.1` review surface and local TEST_ONLY evidence. It does not provide a public-registry package, operational address, customer Sandbox, or credentials.

- Fixed synthetic credit-review case only
- Opaque SignalBriefRef values instead of source bodies
- Authority remains NONE on every output
- No execution, approval, or deployment path

## Trace one case from boundary to review state

1. **Fix the case boundary** — Read tenant, case ID, version, scope, owner, and time range first.
2. **Check the evidence reference** — Confirm that SignalRef holds only the HARBINGER opaque reference and digest, not copied source material.
3. **Compare options and dissent** — Follow which evidence supports or challenges each Option, Assumption, Scenario, and Dissent.
4. **Read the review state** — See how COUNTEREVIDENCE creates a ReviewTrigger and returns the case to REVIEW_REQUIRED.
5. **Confirm the authority boundary** — A Decision record or ELIGIBLE reference still leaves authority at NONE.

- [Open the credit-deterioration example](/docs/polya/examples/credit-deterioration) — Synthetic fixture · not customer data or a real company

## Completion criteria

You are done when you can explain the case question, options, assumptions, counterevidence, open work, and review trigger without breaking lineage. You do not need to decide which option should win.

> **Authority:** PÓLYA validates a decision structure. It does not issue a decision, approval, or execution right.

---

Published route: /docs/polya/getting-started