List DeepL's supported source and target languages via pay-per-call MPP endpoint.
What it does
The DeepL Languages endpoint (`/deepl/languages`) returns the list of languages supported by the DeepL translation service. It is part of a broader DeepL MPP (Micropayment Protocol) gateway hosted by Locus that also exposes translation and rephrasing endpoints. This specific endpoint accepts a POST request with an optional `type` parameter ("source" or "target") and returns the available language codes.
Payment is handled via the Tempo L2 micropayment method at a fixed cost of 5000 base units of pathUSD (6 decimals), which works out to $0.005 per call. The currency is identified by the on-chain address `0x20c000000000000000000000b9537d11c60e8b50`. The endpoint is a POST-only route; HEAD and GET probes returned 404, which is expected given the OpenAPI spec declares only a POST method.
The sibling endpoints on the same gateway include `/deepl/translate` (text translation across 30+ languages with options for formality, context, model type, and markup handling) and `/deepl/rephrase` (DeepL Write for text improvement with style and tone controls), both priced at $0.025+ scaling with text length. Documentation is referenced at `https://beta.paywithlocus.com/mpp/deepl.md` and the upstream DeepL API reference at `https://developers.deepl.com`.
Capabilities
Use cases
- —Querying available source and target languages before submitting a translation request
- —Building dynamic language selectors in translation UIs
- —Validating language codes programmatically before calling the translate endpoint
Fit
Best for
- —Agents that need to discover supported languages before translating
- —Applications integrating DeepL translation via micropayments without an API key
- —Lightweight metadata lookups for translation workflows
Not for
- —Actual text translation (use the /deepl/translate sibling endpoint instead)
- —High-volume bulk language list caching where a static list would suffice
- —Users who need free access — every call costs $0.005
Quick start
curl -X POST https://deepl.mpp.paywithlocus.com/deepl/languages \
-H "Content-Type: application/json" \
-d '{"type": "target"}'Example
Request
{
"type": "target"
}Endpoint
Quality
The OpenAPI spec provides a clear schema, pricing, and endpoint description. However, the probe returned 404 on HEAD/GET (expected for a POST-only route) so no live 402 challenge was captured. No example response is available, and crawl pages all returned generic 'not found' messages. The endpoint is likely live for POST but this could not be directly confirmed.
Warnings
- —Probe did not capture a 402 challenge because only HEAD and GET were attempted on a POST-only endpoint — liveness not fully confirmed.
- —No example response body is available; the response schema is undocumented beyond '200: Successful response'.
- —The currency address 0x20c000000000000000000000b9537d11c60e8b50 is assumed to be pathUSD with 6 decimals based on the Tempo method convention; if decimals differ, the $0.005 price would be incorrect.
Citations
- —The /deepl/languages endpoint costs 5000 base units via Tempo settlementhttps://deepl.mpp.paywithlocus.com
- —DeepL supports 30+ languages for translationhttps://deepl.mpp.paywithlocus.com
- —API reference available at developers.deepl.comhttps://developers.deepl.com
- —LLM-oriented docs at beta.paywithlocus.com/mpp/deepl.mdhttps://beta.paywithlocus.com/mpp/deepl.md