guard sql derived

{
  "input": {
    "body": {
      "sql": "SELECT id, total FROM analytics.orders ORDER BY created_at DESC LIMIT 100",
      "policy": {
        "max_rows": 1000,
        "read_only": true,
        "allowed_tables": [
          "analytics.orders"
        ],
        "allowed_schemas": [
          "analytics"
        ],
        "allowed_functions": [
          "count",
          "sum",
          "avg"
        ],
        "allow_multi_statement": false
      },
      "dialect": "postgresql",
      "audience": "executor:acme-prod-01",
      "issue_permit": true,
      "target_pg_major": 18
    },
    "type": "http",
    "method": "POST",
    "bodyType": "json"
  },
  "output": {
    "type": "json",
    "example": {
      "ok": true,
      "result": {
        "permit": "eyJhbGciOiJFZDI1NTE5Iiwia2lkIjoi…",
        "grammar": "pg18/libpg-query@18.1.4",
        "findings": [],
        "stmt_hash": "sha256:0f4c1d8e2b7a9c5d3e6f8a1b2c4d5e6f7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d",
        "permit_kid": "uGzLTTwi4LTsOiBLgwf2wMU7ILTecj18Y_71Y37bVD8",
        "obligations": {
          "max_rows": 1000,
          "require_read_only_tx": true,
          "statement_timeout_ms": 30000
        },
        "policy_hash": "sha256:2b7a9c5d3e6f8a1b2c4d5e6f7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d0f4c1d8e",
        "classification": "read_only",
        "normalized_sql": "SELECT id, total FROM analytics.orders ORDER BY created_at DESC LIMIT 100",
        "statement_count": 1,
        "statement_types": [
          "SelectStmt"
        ],
        "target_pg_major": 18,
        "stmt_fingerprint": "a1b2c3d4e5f60718",
        "permit_expires_at": "2026-08-03T12:00:45.000Z",
        "referenced_tables": [
          "analytics.orders"
        ],
        "referenced_schemas": [
          "analytics"
        ],
        "referenced_functions": []
      },
      "verdict": "pass",
      "evidence": [],
      "warnings": [
        "stmt_fingerprint is ADVISORY and must not be used for authorization: libpg-query fingerprints discard literal constants, so two statements differing only in a value share one fingerprint. stmt_hash is the binding value."
      ],
      "confidence": 1,
      "risk_codes": [],
      "request_hash": "sha256:1c2d0f4c1d8e2b7a9c5d3e6f8a1b2c4d5e6f7a8b9c0d1e2f3a4b5c6d7e8f9a0b",
      "data_versions": {
        "parser": "libpg-query@18.1.4",
        "grammar": "pg18/libpg-query@18.1.4",
        "pg_parse_version": "180004"
      },
      "policy_version": "sqlpermit-policy-1.0.0"
    }
  }
}