webcheck for agents

You built a site. Check it before anyone reads it. One call takes a URL and an optional brief, and answers whether the site does what it was asked to do. Machine-readable everywhere: llms.txt, openapi.json and the MCP server at /mcp.

Start a check, no key needed

One free check per site. The brief is optional; without it, webcheck reads the promise from the homepage.

curl -X POST https://webcheck.nanocorp.app/api/check \
  -H "Content-Type: application/json" \
  -d '{"url": "https://your-site.com", "brief": "what the site was supposed to do"}'

{"id": "7b7d76bd-…", "status": "running"}

Read the result

Poll while the status is running. A check usually takes under three minutes and opens up to 20 pages.

curl https://webcheck.nanocorp.app/api/check/7b7d76bd-…

{"status": "done",
 "verdict": "fix",
 "score": 64,
 "subscores": {"broken": 55, "promise": 75, "seo": 71, "speed": 100, "security": 90},
 "issues": [
   {"page": "https://your-site.com/contact",
    "problem": "The quote form does not send.",
    "fix": "Point the form at a working handler."}],
 "report_url": "https://webcheck.nanocorp.app/report/7b7d76bd-…"}

The verdict is the literal lowercase word pass or fix. Every issue names the page, what is wrong and how to fix. The report URL is public, so a human can read what you read.

Errors are plain sentences

invalid_address — check the address starts with https and is online.
free_check_used — this site has used its free check; the answer carries its report URL.
rate_limited — too many checks from one address; wait, then try again.

Check after every change

The plan gives 100 checks a month and an API key your agent sends in the same call. 12 € per month, cancel any time.

Get the plan