On-Page API

SEMUST-API-USER: your_username
SEMUST-API-PASSWORD: your_password
Content-Type: application/json

{
  "type": "lighthouse",
  "url": "https://www.python.org/",
  "device": "mobile"
}

{
  "type": "audit",
  "url": "https://www.python.org/",
  "javascript": true
}

{
  "type": "content",
  "url": "https://www.python.org/",
  "markdown": true
}

curl -X POST https://data.semust.com/v1/on-page \
  -H "SEMUST-API-USER: your_username" \
  -H "SEMUST-API-PASSWORD: your_password" \
  -H "Content-Type: application/json" \
  -d '{"type": "lighthouse", "url": "https://www.python.org/", "device": "mobile"}'

import requests

response = requests.post(
    "https://data.semust.com/v1/on-page",
    headers={
        "SEMUST-API-USER": "your_username",
        "SEMUST-API-PASSWORD": "your_password",
    },
    json={"type": "lighthouse", "url": "https://www.python.org/"},
    timeout=90,  # longer than ?wait= (60 seconds by default)
)

data = response.json()
if response.status_code == 202:
    # Still running. Collect it later from data["poll_url"],
    # or use the call() helper from the Tasks page.
    raise SystemExit(f"Task {data['task_id']} is still running")
if response.status_code != 200:
    # PAGE_BLOCKED / PAGE_UNAVAILABLE: the page could not be checked (not charged)
    raise SystemExit(f"{data['code']}: {data['error']} {data.get('hint', '')}")

print(data["data"]["scores"])
for audit in data["data"]["failed_audits"]:
    print(audit["category"], audit["title"], audit["display_value"])

{
  "success": true,
  "type": "lighthouse",
  "url": "https://www.python.org/",
  "device": "desktop",
  "categories": ["performance", "accessibility", "best_practices", "seo"],
  "language": "tr",
  "data": {
    "final_url": "https://www.python.org/",
    "lighthouse_version": "13.4.0",
    "fetched_at": "2026-11-07T03:08:11Z",
    "scores": { "performance": 94, "accessibility": 79, "best_practices": 100, "seo": 92 },
    "metrics": {
      "first_contentful_paint_ms": 641,
      "largest_contentful_paint_ms": 1085,
      "total_blocking_time_ms": 0,
      "cumulative_layout_shift": 0.122,
      "speed_index_ms": 641,
      "time_to_interactive_ms": 1085
    },
    "failed_audits": [
      {
        "id": "render-blocking-insight",
        "category": "performance",
        "title": "Oluşturma engelleme istekleri",
        "description": "İstekler sayfanın ilk oluşturma işlemini engelliyor…",
        "score": 0,
        "display_value": "Tahmini tasarruf: 370 ms.",
        "savings_ms": 350,
        "savings_bytes": null
      },
      {
        "id": "unused-css-rules",
        "category": "performance",
        "title": "Kullanılmayan CSS'yi azaltın",
        "description": "Ağ etkinliğinin kullandığı bayt sayısını azaltmak üzere…",
        "score": 0,
        "display_value": "Tahmini tasarruf: 125 KiB",
        "savings_ms": 120,
        "savings_bytes": 128464
      },
      {
        "id": "color-contrast",
        "category": "accessibility",
        "title": "Arka plan ve ön plan renkleri yeterli kontrast oranına sahip değil.",
        "description": "Birçok kullanıcı, düşük kontrastlı metni okumakta zorlanır…",
        "score": 0,
        "display_value": null,
        "savings_ms": null,
        "savings_bytes": null
      }
    ],
    "passed_count": 53,
    "failed_count": 18,
    "warnings": []
  },
  "cost": 0.0055,
  "cached": false,
  "request_id": "0b7e6f1a-3c2d-4e5f-9a8b-1c2d3e4f5a6b"
}

{
  "success": true,
  "type": "audit",
  "url": "https://www.python.org/",
  "javascript": true,
  "data": {
    "final_url": "https://www.python.org/",
    "status_code": 200,
    "score": 98.17,
    "title": "Welcome to Python.org",
    "description": "The official home of the Python Programming Language",
    "canonical": null,
    "h1": ["Functions Defined", "All the Flow You’d Expect", "Compound Data Types"],
    "headings": { "h1": 5, "h2": 9, "h3": 0, "h4": 0, "h5": 0, "h6": 0 },
    "word_count": 537,
    "readability": 56.6,
    "links": { "internal": 66, "external": 67 },
    "images": 1,
    "scripts": 7,
    "stylesheets": 0,
    "size_bytes": 53822,
    "transfer_bytes": 11718,
    "load_time_ms": 173,
    "timing": {
      "connect_ms": 20,
      "waiting_ms": 11,
      "download_ms": 1,
      "dom_complete_ms": 172,
      "time_to_interactive_ms": 156
    },
    "issues": ["title_too_short", "render_blocking_resources", "low_content_rate", "no_image_title"],
    "fetched_at": "2026-11-07T03:07:49Z"
  },
  "cost": 0.00165,
  "cached": false,
  "request_id": "5d4c3b2a-1f0e-4d9c-8b7a-6f5e4d3c2b1a"
}

{
  "success": true,
  "type": "content",
  "url": "https://www.python.org/",
  "markdown": true,
  "data": {
    "title": "Functions Defined",
    "language": "en",
    "sections": [
      {
        "level": 1,
        "heading": "Functions Defined",
        "text": "The core of extensible programming is defining functions.\nPython allows mandatory and optional arguments, keyword arguments,\nand even arbitrary argument lists. More about defining functions"
      }
    ],
    "secondary_sections": [
      { "level": 2, "heading": "Latest News", "text": "More news" }
    ],
    "word_count": 286,
    "contacts": { "emails": [], "phones": [] },
    "markdown": "# Functions Defined\n## >>> Python Software Foundation\n\n…"
  },
  "cost": 0.000165,
  "cached": false,
  "request_id": "9a8b7c6d-5e4f-4a3b-2c1d-0e9f8a7b6c5d"
}

{
  "error": "The site refused the request (HTTP 403)",
  "code": "PAGE_BLOCKED",
  "field": "url",
  "hint": "Bot protection (such as Cloudflare) often blocks automated checks. Allow it for this check or try another page. You were not charged",
  "retryable": false,
  "request_id": "3f2b1c4d-0000-4000-8000-000000000001"
}

{
  "error": "The page could not be loaded",
  "code": "PAGE_UNAVAILABLE",
  "field": "url",
  "hint": "The page answered with HTTP 404. You were not charged",
  "retryable": false,
  "request_id": "3f2b1c4d-0000-4000-8000-000000000002"
}