# Null Coverage — String Normalisation + Equal-Width Histogram

> Null Coverage — String Normalisation + Equal-Width Histogram is a paid API for AI agents from market.datapackvibe.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-18).

Runs two local analytical reports — string normalisation and an equal-width histogram — on null coverage records (missing_values, total_values) for up to 200 rows.

## Facts

- Endpoint: POST https://market.datapackvibe.com/x402/assistant-ib26-analytics-03-031?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/null-coverage-string-normalisation-equal-width-histogram-45f97098
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_4YyB9x6PFZLCWXAiam1KH

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 null-coverage-string-normalisation-equal-width-histogram-45f97098 -d '<json body>'
```

Example prompt: Take my null coverage records — I have 4 rows across group-a and group-b with missing_values and total_values — normalize the missing_values field strings and build a 5-bin equal-width histogram for it.

## When to prefer this

Choose this endpoint when you need two lightweight analytical reports — string normalisation plus a histogram — specifically on null coverage data (missing_values and total_values fields), all computed locally without any external API calls, predictions, or professional assessments. It is ideal for data quality pipelines, QA workflows, or profiling jobs where you want a cheap, fast, self-contained analysis of up to 200 rows for $0.01 USDC.

## Known failure modes

- Rows array is empty or exceeds 200 items — validation error
- missing_values or total_values contain values outside ±1,000,000,000,000 — rejected
- bins parameter set outside 1–30 range — validation error
- Required row fields (row_id, date, dataset_group) missing or malformed — schema error
- Date strings not matching YYYY-MM-DD pattern — pattern validation failure
- field enum value not one of missing_values or total_values — rejected

## How this service works

Null coverage — String normalisation + Equal-width histogram: String normalisation + Equal-width histogram for supplied null coverage records (missing_values, total_values). Up to 200 rows; 2 independent reports using shared local analytical engines. No live lookup, prediction, professional assessment or external action. 0.01 USDC includes 2 supplied-data reports for up to 200 rows.

## Output

Returns two independent analytical reports: (1) a string normalisation report showing standardised representations of the chosen field values, and (2) an equal-width histogram report with bin edges, bin counts, and distribution summary — all computed locally without any external lookups or predictions.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "bins": {
   "type": "integer",
   "default": 5,
   "maximum": 30,
   "minimum": 1
  },
  "rows": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "row_id",
     "dataset_group",
     "date",
     "missing_values",
     "total_values"
    ],
    "properties": {
     "date": {
      "type": "string",
      "default": "",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
      "maxLength": 10
     },
     "row_id": {
      "type": "string",
      "default": "",
      "maxLength": 80,
      "minLength": 1
     },
     "total_values": {
      "type": [
       "number",
       "null"
      ],
      "maximum": 1000000000000,
      "minimum": -1000000000000
     },
     "dataset_group": {
      "type": "string",
      "default": "",
      "maxLength": 80
     },
     "missing_values": {
      "type": [
       "number",
       "null"
      ],
      "maximum": 1000000000000,
      "minimum": -1000000000000
     }
    },
    "additionalProperties": false
   },
   "default": [
    {
     "date": "2026-10-01",
     "row_id": "row-1",
     "total_values": 1,
     "dataset_group": "group-a",
     "missing_values": 10
    },
    {
     "date": "2026-10-02",
     "row_id": "row-2",
     "total_values": 2,
     "dataset_group": "group-b",
     "missing_values": 20
    },
    {
     "date": "2026-10-03",
     "row_id": "row-3",
     "total_values": 3,
     "dataset_group": "group-a",
     "missing_values": 15
    },
    {
     "date": "2026-10-04",
     "row_id": "row-4",
     "total_values": 4,
     "dataset_group": "group-b",
     "missing_values": 30
    }
   ],
   "maxItems": 200,
   "minItems": 1
  },
  "field": {
   "enum": [
    "missing_values",
    "total_values"
   ],
   "type": "string",
   "default": "missing_values"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/null-coverage-string-normalisation-equal-width-histogram-45f97098/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)