# Button Labels Prior Text-Set Comparison

> Button Labels Prior Text-Set Comparison is a paid API for AI agents from market.datapackvibe.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-21).

Extracts button labels from a webpage or HTML snippet and compares them against a supplied set of previous text values to identify changes

## Facts

- Endpoint: POST https://market.datapackvibe.com/x402/assistant-bx-web-buttons-compare?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/button-labels-prior-text-set-comparison-b49b3abf
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ItkwNH2fFGbIYNN7hziSJ

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 button-labels-prior-text-set-comparison-b49b3abf -d '<json body>'
```

Example prompt: Check if the button with id 'sample' on https://example.com/product still says 'Example product guide' — compare it against these previous labels: ['Buy Now', 'Add to Cart'] and filter by the term 'product'.

## When to prefer this

Use this endpoint when you need to detect whether button labels on a static HTML page have changed relative to a known prior set of text values, especially for regression testing, UI monitoring, or content auditing workflows. It is purpose-built for button-specific text comparison rather than general DOM diffing or full-page change detection.

## Known failure modes

- URL is unreachable or returns non-200 status — parsing fails with error
- HTML exceeds 100,000 character limit — request rejected
- No button found matching specified attribute and attribute_value — empty result
- JavaScript-rendered buttons not visible — static parser only, dynamic content missed
- Invalid attribute pattern (must start with a letter, alphanumeric/dash/colon/underscore) — validation error
- previous_texts array exceeds 200 items — request rejected

## How this service works

Button labels — Prior text-set comparison: Prior text-set comparison for Button labels. One public HTTPS page or supplied HTML; static parsing, no JavaScript rendering, login or access bypass. Specialised preset in a shared 50-profile, 20-operation engine. 0.01 USDC includes one bounded prior text-set comparison result.

## Output

Returns a bounded prior text-set comparison result indicating whether the current button label(s) found on the page or HTML match, partially match, or differ from the supplied previous_texts list, along with details about the matched attribute and term scope.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "default": "",
   "maxLength": 2048
  },
  "html": {
   "type": "string",
   "default": "<!doctype html><html><head></head><body><button id=\"sample\" data-kind=\"example\">Example product guide</button></body></html>",
   "maxLength": 100000
  },
  "term": {
   "type": "string",
   "default": "product",
   "maxLength": 100,
   "minLength": 1
  },
  "attribute": {
   "type": "string",
   "default": "id",
   "pattern": "^[a-zA-Z][a-zA-Z0-9:_-]{0,49}$",
   "maxLength": 50
  },
  "previous_texts": {
   "type": "array",
   "items": {
    "type": "string",
    "default": "",
    "maxLength": 1000
   },
   "default": [
    "Older example"
   ],
   "maxItems": 200,
   "minItems": 0
  },
  "attribute_value": {
   "type": "string",
   "default": "sample",
   "maxLength": 200
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/button-labels-prior-text-set-comparison-b49b3abf/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)