DeepL MCP server
DeepL's official MCP server: high-quality machine translation, document translation, and AI rephrasing across 30+ languages from your agent.
The DeepL MCP server is DeepL's official integration that gives a coding agent direct access to the DeepL API — widely regarded as one of the most accurate machine-translation engines available. Instead of pasting text into a separate tool, the agent can translate strings and whole documents, rephrase text to change its style or tone, and inspect which source and target languages are supported, all inside its normal tool-calling loop. It is ideal for localizing UI strings, README files, error messages, and product copy, or for cleaning up and restyling drafted text.
The server runs locally over stdio via npx (deepl-mcp-server) and authenticates with a DEEPL_API_KEY from your DeepL account; the key works with both the free and pro API plans. Beyond plain translation it exposes glossary tools so the agent can list glossaries, read their metadata, and pull dictionary entries to keep terminology consistent across a project, plus document translation that preserves formatting. The write-friendly rephrase tool is backed by DeepL's Write capability, with helpers to enumerate the available writing styles and tones so the agent can pick the right register before rewriting.
Quick install
Copy-paste configs are provided for all 8 supported clients. Pick your client below.
Add to ~/.claude.json
{
"mcpServers": {
"deepl": {
"command": "npx",
"args": [
"-y",
"deepl-mcp-server"
],
"env": {
"DEEPL_API_KEY": "<DEEPL_API_KEY>"
}
}
}
}claude mcp add deepl -- npx -y deepl-mcp-serverAvailable tools
| Tool | Description |
|---|---|
| get-source-languages | Get the list of source languages available for translation, with names and ISO-639 codes. |
| get-target-languages | Get the list of target languages available for translation, with names and ISO-639 codes. |
| translate-text | Translate text into a target language, with optional formality control. |
| translate-document | Translate a document while preserving its formatting. |
| rephrase-text | Rephrase text in the same or a different language, optionally adjusting writing style and tone. |
| list-glossaries | Get the list of all glossaries and their associated metadata. |
| get-glossary-info | Get metadata about a specific glossary by id. |
| get-glossary-dictionary-entries | Retrieve the entries from a glossary dictionary for a language pair. |
| get-writing-styles | Get the writing styles available for use with the rephrase-text tool. |
| get-writing-tones | Get the writing tones available for use with the rephrase-text tool. |
Required configuration
- DEEPL_API_KEYRequired
DeepL API key from your DeepL account. Works with the free or pro API plan. Required.
What you can do with it
Localize a codebase in the agent loop
Point the agent at your i18n strings and let it call translate-text into each target language, using get-target-languages to confirm coverage and a glossary to keep product terms consistent across locales.
Translate documents and restyle copy
Translate a formatted document with translate-document so layout is preserved, then run rephrase-text to adjust the tone of marketing or support copy after checking get-writing-styles and get-writing-tones.
FAQ
- Is it free?
- The MCP server is open source and free, and it works with DeepL's free API plan (with a monthly character allowance) as well as paid pro plans. Translation and rephrasing are billed by DeepL per character against your DEEPL_API_KEY.
- Does it support remote/OAuth?
- The canonical mode is local stdio via npx with an API key; there is no OAuth flow. The DEEPL_API_KEY determines whether you hit the free or pro DeepL API endpoint.