# Evaluate coverage criteria
URL: https://backworkhealth.com/docs/api/evaluateCoverage

Evaluate an active policy's structured coverage criteria (logic AST) against rule-level parameters.

**Endpoint:** `POST /api/v1/coverage/evaluate`

**Availability:** Live in production.

**Authentication:** API key in `Authorization: Bearer <key>` with the `read` scope.

Evaluate an active policy's structured coverage criteria (logic AST) against rule-level parameters. Returns whether the criteria are met, a confidence score, and detailed reasons. Coverage requires every evaluated criteria block to pass. Patient identifiers are rejected with `PHI_NOT_ALLOWED`.

**Parameters**

* `policy_id` (body, required): The policy identifier
* `parameters` (body, required): Rule-level, non-identifying parameters to evaluate against the policy's criteria

**Example request**

```bash
curl -X POST "https://backworkhealth.com/api/v1/coverage/evaluate" \
  -H "Authorization: Bearer $BACKWORK_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "policy_id": "L33831",
  "parameters": {}
}'
```

**Example response** (`200`)

```json
{
  "success": true,
  "data": {
    "covered": true,
    "confidence": 0.85,
    "requires_manual_review": true,
    "reasons": [
      "string"
    ],
    "matched_criteria": [
      "string"
    ],
    "unmatched_criteria": [
      "string"
    ],
    "skipped_criteria": [
      "string"
    ],
    "blocks_evaluated": 0,
    "blocks_without_ast": 0,
    "policy": {
      "policy_id": "string",
      "title": "string",
      "policy_type": "string",
      "applicability_scope": "shared_markets",
      "applicability_markets": [
        "string"
      ],
      "applicability_evidence": {
        "document_sha256": "string",
        "market_index_listings": [
          {}
        ],
        "document_statements": [
          {}
        ]
      },
      "applicability_note": "string",
      "public_url": "https://backworkhealth.com/policy/L33831",
      "source_check": {
        "source_url": "https://www.cms.gov/medicare-coverage-database/view/lcd.aspx?lcdid=33831",
        "last_fetched_at": "2026-01-15T10:30:00Z",
        "content_sha256": "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08",
        "source_accuracy": [
          {}
        ]
      }
    }
  },
  "meta": {
    "request_id": "string",
    "timestamp": "2026-01-15T10:30:00Z",
    "attributions": {
      "disclaimer": "string",
      "cpt": "string",
      "loinc": "string",
      "cms": "string",
      "payer_data": "string",
      "negotiated_rates": "string"
    },
    "disclaimer": "string"
  }
}
```