# API Usage Two-Measure Correlation

> API Usage Two-Measure Correlation is a paid API for AI agents from market.datapackvibe.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-19).

Computes the statistical correlation between API request counts and latency measurements across up to 200 typed records, locally, without external enrichment.

## Facts

- Endpoint: POST https://market.datapackvibe.com/x402/assistant-sector-analytics-api-usage-correlation?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-usage-two-measure-correlation-c1d11270
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Mjfqaend6r7EiaflVdQG3

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability api-usage-two-measure-correlation-c1d11270 -d '<json body>'
```

Example prompt: Can you run a two-measure correlation on my API usage data to see how request counts relate to latency? Here are up to 200 rows with endpoint names, dates, request counts, and latency in milliseconds — I want to know how strongly these two metrics are correlated.

## When to prefer this

Choose this endpoint when you need a fast, local statistical correlation between exactly two numeric API usage metrics (request count and latency) across up to 200 records, without requiring external data enrichment, forecasting, or multi-measure analysis. It is ideal for lightweight performance diagnostics and load-latency relationship checks at low cost ($0.01 USDC per call).

## Known failure modes

- Fewer than 1 row submitted — minimum item count not met
- More than 200 rows submitted — exceeds maxItems limit
- Missing required fields (row_id, endpoint, date, requests, latency_ms) — validation error
- Date field not matching YYYY-MM-DD pattern — schema validation failure
- Numeric values outside allowed range — schema rejection
- All numeric values null — insufficient data to compute correlation

## How this service works

API usage - Two-measure correlation: Two-measure correlation for API usage. Up to 200 supplied typed records. Local numeric and data-quality processing; no external enrichment or forecasting. One of 25 profiles or calculations across 20 shared operations in this sector. 0.01 USDC includes one bounded two-measure correlation deliverable.

## Output

Returns a bounded correlation deliverable containing the computed correlation coefficient between the two supplied numeric measures (requests and latency_ms), along with data-quality metadata derived from the submitted rows. All processing is local with no external enrichment or forecasting.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "rows": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "row_id",
     "endpoint",
     "date",
     "requests",
     "latency_ms"
    ],
    "properties": {
     "date": {
      "type": "string",
      "default": "",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
      "maxLength": 10
     },
     "row_id": {
      "type": "string",
      "default": "",
      "maxLength": 80,
      "minLength": 1
     },
     "endpoint": {
      "type": "string",
      "default": "",
      "maxLength": 80
     },
     "requests": {
      "type": [
       "number",
       "null"
      ],
      "maximum": 1000000000000,
      "minimum": -1000000000000
     },
     "latency_ms": {
      "type": [
       "number",
       "null"
      ],
      "maximum": 1000000000000,
      "minimum": -1000000000000
     }
    },
    "additionalProperties": false
   },
   "default": [
    {
     "date": "2026-10-01",
     "row_id": "row-1",
     "endpoint": "group-a",
     "requests": 10,
     "latency_ms": 1
    },
    {
     "date": "2026-10-02",
     "row_id": "row-2",
     "endpoint": "group-b",
     "requests": 20,
     "latency_ms": 2
    },
    {
     "date": "2026-10-03",
     "row_id": "row-3",
     "endpoint": "group-a",
     "requests": 15,
     "latency_ms": 3
    },
    {
     "date": "2026-10-04",
     "row_id": "row-4",
     "endpoint": "group-b",
     "requests": 30,
     "latency_ms": 4
    }
   ],
   "maxItems": 200,
   "minItems": 1
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-usage-two-measure-correlation-c1d11270/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from market.datapackvibe.com](https://www.zero.xyz/host/market.datapackvibe.com/llms.txt)