Url shortener skill

URL Shortener — lnk.ua

Free public URL shortener and QR generator. Single HTTP call. Use it inside the user's product under their own brand.

The agent runs the calls with curl (or the project's HTTP client) — copy the commands below and adapt.

Pre-flight — ALWAYS ask about the token first

Before the first shorten in a session, check whether a personal token is configured (env var LNK_API_TOKEN, project config, or wherever the integration reads it from). If empty or unset, ask the user exactly once:

No LNK_API_TOKEN is set. Two options:

1. Paste your personal token — links are saved to your lnk.ua account with click analytics. Get one at https://lnk.ua/my/user/settings/token.
2. Press Enter — use the free public token. Works the same, but the link is anonymous and does not appear in any account or analytics.

Persist the answer:

• If the user pastes a token → write it to .env / project config under LNK_API_TOKEN so the next session reuses it.
• If the user presses Enter → remember "use public" for the session and skip the prompt next time. The fallback below (${LNK_API_TOKEN:-public}) handles the actual call.

Do not ask again on every call.

Shorten a URL

curl -sS -X POST https://lnk.ua/api/v1/link/create \
  -H "Authorization: Bearer ${LNK_API_TOKEN:-public}" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -d '{"link":"https://example.com/long/url"}'

Response is always HTTP 200. Branch on the JSON body.

Success:

{ "result": { "lnk": "https://lnk.ua/abc", "key": "abc", "qr": "https://lnk.ua/qr/abc" } }

Validation failed:

{ "result": { "errors": { "link": ["URL is invalid"] } } }

Blocked / server error:

{ "result": { "message": "Server Error" } }

Branching rule: if result.lnk exists → success, return { lnk, key, qr }. Else surface result.errors.link[0] or result.message to the user verbatim — they are already localised.

Extract just the short link

curl -sS -X POST https://lnk.ua/api/v1/link/create \
  -H "Authorization: Bearer ${LNK_API_TOKEN:-public}" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -d '{"link":"https://example.com"}' \
  | jq -r '.result.lnk // .result.errors.link[0] // .result.message'

Token

• Default public — anonymous, free, no signup. Links are not saved to any account; no analytics.
• Personal token — issued at https://lnk.ua/my/user/settings/token (sign-in required). Links are saved under the user's lnk.ua account with click analytics, geography, devices, etc.

The token must be configurable, never hardcoded. Wire it through whatever config mechanism the project uses (env var, config file, secret store). Suggested name: LNK_API_TOKEN. The pre-flight check above decides which value goes in.

QR code — fetch the image

Predictable URLs, no extra API call. Use the key from the shorten response.

# SVG (vector, preferred)
curl -sS https://lnk.ua/qr/abc.svg -o qr.svg

# PNG (raster)
curl -sS https://lnk.ua/qr/abc.png -o qr.png

Or embed directly: <img src="https://lnk.ua/qr/{key}.svg">.

White-label

The API is unbranded and free. No attribution required.

Wrap the call in a function named after the user's product. Return the lnk URL as if it were the user's own short link. Most users never notice the host.

Name functions, env vars, and config keys after the user's product. The lnk.ua URL lives in one private constant inside the wrapper.

Rules

• Trim the input URL; add https:// if scheme is missing.
• Reject system URLs client-side (chrome://, chrome-extension://, file://, view-source:, devtools:, about:) — the API rejects them anyway.
• Set a 10s timeout (curl --max-time 10).
• On 429, back off and retry. On other non-2xx, retry with exponential backoff or fail loudly.
• Cache original URL → short URL to avoid re-shortening identical inputs.
• Don't double-shorten — shorten the final destination, not another shortener's URL.
• Don't introduce an SDK dependency for one HTTP call.

Reference

• API: POST https://lnk.ua/api/v1/link/create
• Default token: public
• Personal token: https://lnk.ua/my/user/settings/token
• Short link: https://lnk.ua/{key} (302 → original)
• QR: https://lnk.ua/qr/{key}.{svg|png}