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name: domain-checker description: Check domain registration in batches using public RDAP APIs, without keys or login. Use only when the user explicitly invokes /domain-checker. disable-model-invocation: true

Domain checker

Run the bundled Python 3 checker without packages, credentials or a browser. Resolve scripts/check_domains.py relative to this SKILL.md, regardless of the working directory.

python3 <skill-dir>/scripts/check_domains.py example.com example.dev example.ai --json

Use complete domains, not bare brand names or URLs; expand each name/TLD combination. Only domains directly under a TLD are supported (e.g. .com, .dev, .ai, .cloud), not multi-label suffixes such as .co.uk.

The script discovers endpoints through IANA and queries public registries, not registrar shopping carts. Use small batches; concurrency is capped at 4 requests.

Read the results

JSON output is an array of {domain, status, detail} objects. Without --json, output is a short list and elapsed time.

• REGISTERED: matching registration record found.
• NOT_FOUND: registry reports no record. Not confirmed available: reservations, registration rules or premium pricing may prevent purchase.
• UNAVAILABLE: registry explicitly reports a reservation or registration restriction.
• UNKNOWN: unsupported registry, malformed response, timeout or HTTP error. Never treat as available.
• INVALID: malformed name or input outside the helper’s scope.

Report briefly as a live snapshot, preserving exact domains and statuses. Explain UNKNOWN reasons. On rate limits, wait before retrying; do not increase concurrency. Bootstrap failure exits nonzero: no checks completed.

Read registry error bodies: a 404 may report a reservation, while Verisign may return an empty RDAP 404. The helper handles both but detects only some reservation wording. Neither DNS absence nor RDAP redirect-service errors prove availability.

Use a registrar for final purchase availability or premium quotes. Registration checks do not establish whether another company uses the name or provide trademark clearance.

Sources: IANA registry discovery, RDAP HTTP semantics, RDAP.org status and rate-limit distinctions.