# Halowerk Add-to-Cart Experiment Plan

> Halowerk Add-to-Cart Experiment Plan is a paid API for AI agents from conversion.halowerk.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-11-03).

Fetches public evidence from a target URL and evaluates it against documented add-to-cart conversion criteria, returning an observation, threshold, verdict, evidence source, limitations, and a recommended experiment action.

## Facts

- Endpoint: POST https://conversion.halowerk.com/v1/add-to-cart-experiment?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-11-03
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-add-to-cart-experiment-plan-4222a228
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Z2Jzh7NsHjZFeZgeNgxMP

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 halowerk-add-to-cart-experiment-plan-4222a228 -d '<json body>'
```

Example prompt: Can you run an add-to-cart experiment plan on https://shop.example.com/products/widget and tell me whether the add-to-cart action passes the conversion criteria, what the evidence says, and what experiment I should run next?

## When to prefer this

Choose this endpoint when you need a passive, non-destructive experiment plan specifically focused on the add-to-cart action on a public product page. It is distinct from the audit and decision siblings in that it returns an actionable experiment recommendation rather than just a verdict or audit log. Prefer this when you want to know not just whether the add-to-cart element passes criteria, but what experiment to run next.

## Known failure modes

- Target URL is unreachable or returns a non-200 status — endpoint may return an error or inconclusive verdict
- Target page requires authentication, making add-to-cart elements invisible to passive inspection
- Add-to-cart element is dynamically rendered and not present in the crawled HTML, limiting evidence
- Malformed or non-HTTP(S) URL provided, triggering a validation error
- Rate limiting or bot-blocking by the target server preventing evidence retrieval

## How this service works

Add-to-cart action experiment plan fetches current public evidence from the supplied target and evaluates the documented criterion. It returns the observation, threshold, verdict, exact evidence source, limitations and a mode-specific action. The check is passive: no login attempt, payload injection, exploit, purchase, form submission or load test is performed.

## Output

Returns a structured report containing the observed add-to-cart evidence gathered from the target URL, the evaluation threshold, a pass/fail/inconclusive verdict, the exact source of the evidence, any limitations of the passive inspection, and a mode-specific recommended experiment action. No login, purchase, or form submission is performed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "target": {
   "type": "string",
   "maxLength": 2048,
   "minLength": 3,
   "description": "Public HTTP(S) URL or domain to inspect. A bare domain is normalized to HTTPS."
  },
  "context": {
   "type": "object",
   "description": "Optional non-secret correlation labels returned unchanged only in the request lifecycle.",
   "maxProperties": 12,
   "additionalProperties": {
    "type": [
     "string",
     "number",
     "boolean",
     "null"
    ]
   }
  },
  "baseline": {
   "type": [
    "object",
    "null"
   ],
   "description": "Optional baseline returned by a previous snapshot call.",
   "additionalProperties": true
  },
  "compare_url": {
   "type": "string",
   "maxLength": 2048,
   "minLength": 3,
   "description": "Optional public comparison URL. Used by change and monitoring services."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/halowerk-add-to-cart-experiment-plan-4222a228/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from conversion.halowerk.com](https://www.zero.xyz/host/conversion.halowerk.com/llms.txt)