# Proofline CTA Check

> Proofline CTA Check is a paid API for AI agents from proofline-audit.chrismellado.chatgpt.site, paid per call via x402, $0.1/call, status unknown (last checked 2026-10-18).

Analyzes a public landing page URL for conversion friction, returning a score, verdict, and prioritized repair recommendations for the call-to-action.

## Facts

- Endpoint: GET https://proofline-audit.chrismellado.chatgpt.site/api/x402/cta-check?utm_source=zero.xyz
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/proofline-cta-check-8c564540
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gmCbg6xNDKh6UFueDt0WI

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 proofline-cta-check-8c564540
```

Example prompt: Can you run a Proofline CTA check on https://myapp.com and tell me what friction is blocking conversions, what score it gets, and what the single most important fix is?

## When to prefer this

Choose this endpoint when you need a fast, evidence-backed, machine-readable audit of a single landing page's call-to-action and conversion friction — especially when you want a prioritized, Linear-ready repair list rather than generic UX advice. Prefer this over general SEO or analytics tools when the goal is specifically diagnosing CTA and conversion flow problems on a public URL.

## Known failure modes

- Non-public or auth-gated URL returns an error or incomplete analysis
- Malformed URL input causes validation failure
- URL that times out or returns non-200 may yield partial or empty results
- JavaScript-heavy SPAs may not be fully inspectable, reducing issue accuracy
- Rate limiting or payment failure returns 402 with no audit result

## How this service works

Evidence-backed product validation and SaaS conversion audits, including a fixed $250 validation sprint with reproducible, Linear-ready defects.

## Output

Returns a JSON object with: an integer score (0–100), a verdict ('clear', 'friction', or 'blocked'), a summary of findings, a list of issues each with id/category/severity/evidence/repair, the highest-priority firstRepair action, and a suggestedCta text string.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string",
       "format": "uri",
       "maxLength": 2048,
       "description": "Public http(s) landing-page URL to inspect"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "product",
      "score",
      "verdict",
      "summary",
      "firstRepair",
      "issues"
     ],
     "properties": {
      "score": {
       "type": "integer",
       "maximum": 100,
       "minimum": 0
      },
      "issues": {
       "type": "array"
      },
      "product": {
       "type": "string"
      },
      "summary": {
       "type": "string"
      },
      "verdict": {
       "enum": [
        "clear",
        "friction",
        "blocked"
       ],
       "type": "string"
      },
      "firstRepair": {
       "type": "string"
      },
      "suggestedCta": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "score": 64,
  "issues": [
   {
    "id": "placeholder-action",
    "repair": "Connect the action to the real next step and verify it on mobile.",
    "category": "action",
    "evidence": "The primary action points to #.",
    "severity": "high"
   }
  ],
  "product": "Proofline CTA Check",
  "summary": "3 evidence-backed friction point(s) found; repair the highest deduction first.",
  "verdict": "friction",
  "firstRepair": "Replace the placeholder CTA destination with the real next step and verify it on mobile.",
  "suggestedCta": "See the product in action"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/proofline-cta-check-8c564540/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from proofline-audit.chrismellado.chatgpt.site](https://www.zero.xyz/host/proofline-audit.chrismellado.chatgpt.site/llms.txt)