metric naming contract audit derived

{
  "input": {
    "body": {
      "samples": [
        {
          "name": "http_requests",
          "type": "counter",
          "labels": {
            "method": "GET",
            "status": "200"
          }
        },
        {
          "name": "http_requests",
          "type": "counter",
          "labels": {
            "method": "GET"
          }
        },
        {
          "name": "queue_depth_total",
          "type": "gauge",
          "labels": {
            "queue": "orders"
          }
        },
        {
          "name": "request_latency_milliseconds",
          "type": "histogram",
          "labels": {
            "le": "0.5"
          }
        },
        {
          "name": "cache_hits_total",
          "type": "counter",
          "labels": {
            "order_id": "8827341"
          }
        },
        {
          "name": "cache_hits_total",
          "type": "counter",
          "labels": {
            "order_id": "8827342"
          }
        },
        {
          "name": "cache_hits_total",
          "type": "counter",
          "labels": {
            "order_id": "8827343"
          }
        },
        {
          "name": "cache_hits_total",
          "type": "counter",
          "labels": {
            "order_id": "8827344"
          }
        },
        {
          "name": "build_info",
          "type": "gauge",
          "labels": {
            "version": "1.4.0"
          }
        }
      ],
      "max_label_cardinality": 3
    },
    "type": "http",
    "method": "POST",
    "bodyType": "json"
  },
  "output": {
    "type": "json",
    "example": {
      "limits": {
        "maxLines": 20000,
        "maxSpans": 10000,
        "maxFields": 500,
        "maxSamples": 20000,
        "maxFindings": 500,
        "maxJsonBytes": 2097152
      },
      "passed": false,
      "metrics": [
        {
          "name": "http_requests",
          "types": [
            "counter"
          ],
          "labels": [
            {
              "label": "method",
              "distinct_values": 1
            },
            {
              "label": "status",
              "distinct_values": 1
            }
          ],
          "samples": 2,
          "label_set_count": 2
        },
        {
          "name": "queue_depth_total",
          "types": [
            "gauge"
          ],
          "labels": [
            {
              "label": "queue",
              "distinct_values": 1
            }
          ],
          "samples": 1,
          "label_set_count": 1
        },
        {
          "name": "request_latency_milliseconds",
          "types": [
            "histogram"
          ],
          "labels": [
            {
              "label": "le",
              "distinct_values": 1
            }
          ],
          "samples": 1,
          "label_set_count": 1
        }
      ],
      "complete": true,
      "findings": [
        {
          "code": "COUNTER_WITHOUT_TOTAL_SUFFIX",
          "detail": "http_requests is a counter and does not end in _total. The convention is what tells a reader a rate is meaningful over it.",
          "metric": "http_requests"
        },
        {
          "code": "UNIT_NOT_IN_NAME",
          "detail": "http_requests carries no unit suffix, so a consumer cannot tell whether it is seconds, milliseconds or something else. The conventional suffixes are seconds, bytes, ratio, celsius, meters.",
          "metric": "http_requests"
        },
        {
          "code": "LABEL_SET_VARIES_BETWEEN_SAMPLES",
          "detail": "http_requests appears with 2 different label sets. A sum or an average over it then groups by whichever labels happen to be present, which is not the grouping anybody asked for.",
          "metric": "http_requests"
        }
      ],
      "conformant": false,
      "request_id": "example-request",
      "service_id": "metric_naming_contract_audit",
      "assumptions": [
        "A varying label set is reported because it makes an aggregate wrong rather than merely incomplete: the sum groups by whichever labels happen to be present, which is an implicit grouping nobody declare...",
        "Cardinality is counted within the samples supplied, so the finding is a floor rather than the true cardinality. The bound is published and the count stops there.",
        "Unit conventions are checked by suffix against a published list, and a sub-second unit is reported because the convention is seconds and every dashboard over it needs a conversion that is easy to omit..."
      ],
      "limitations": [
        "The samples supplied. True cardinality across a whole series, and what any backend charges for it, are outside this.",
        "conformant is true only when every metric was typed and nothing in the naming or labelling was reported."
      ],
      "observed_at": "2026-10-02T00:00:00.000Z",
      "metric_count": 5,
      "not_examined": [],
      "sample_count": 9,
      "finding_count": 10,
      "service_version": "1.0.0",
      "findings_by_code": {
        "UNIT_NOT_IN_NAME": 4,
        "UNIT_NOT_BASE_UNIT": 1,
        "LABEL_HOLDS_IDENTIFIERS": 1,
        "GAUGE_NAMED_AS_A_COUNTER": 1,
        "COUNTER_WITHOUT_TOTAL_SUFFIX": 1,
        "LABEL_CARDINALITY_ABOVE_LIMIT": 1,
        "LABEL_SET_VARIES_BETWEEN_SAMPLES": 1
      },
      "max_label_cardinality": 3
    }
  }
}