I1n Cli MCP Server

Localization as code — CLI and SDK for i1n

Local serverstdioTypeScript

What is the I1n Cli MCP server?

I1n Cli MCP server exists for a simple reason — assistants are far more useful when they can act on I1n Cli directly instead of describing what you should do. Localization as code — CLI and SDK for i1n.

What you get

Localization as code. Push your translation keys, AI translates to 182 languages, pull type-safe TypeScript definitions. Built for developers, AI agents, and product teams.

  • One command — — i1n push --translate es,fr,ja and you're done
  • Type-safe — — auto-generated i1n.d.ts with full IDE autocomplete
  • AI-native — — MCP server for Cursor, Claude Code, Windsurf. Your agent handles i18n for you
  • Zero migration — — Bridge Mode wraps your existing i18next/next-intl/vue-i18n
  • 5x cheaper — — Free tier included. Pro at $29/mo vs Lokalise at $144/mo

Setting it up

The server ships on npm as i1n, so your MCP client can launch it on demand — there is no separate build step. Add the server block to your client's configuration, restart it, and the tools register themselves.

What the assistant can call

Once I1n Cli is connected, these are the calls the assistant has available:

  • Pluralization — Define plural variants with _zero, _one, _other suffixes:
  • Interpolation — Three syntaxes supported universally: {var}, {{var}}, %{var}

Configuration and credentials

You will need one environment variable: STORAGE_KEY. The server will not start without them, which is usually why the tools fail to appear on a first run. Keep credentials in your client's env block or a secrets manager rather than in a file you might commit.

Before you rely on it

  • It runs with your machine's permissions. That is convenient and also the reason to think about what you point it at before you approve a tool call.
  • Missing credentials fail quietly in some clients — if no tools show up, check the environment block first.
  • MCP clients confirm each tool call by default. Leave that on until you have watched what the i1n cli mcp server does with a few real requests.

Choosing this one

This sits in the developer tooling group, where several servers overlap in what they claim to do but differ sharply once you actually set them up. I1n Cli's toolset — Pluralization, Interpolation — is a fair guide to whether it matches your workflow. It is maintained by pakvothe; worth a glance at recent repository activity before you build anything load-bearing on it.

This entry was verified against I1n Cli's own documentation before publication; SyncDev keeps the directory reviewed rather than auto-generated.

Available tools

ToolWhat it does
PluralizationDefine plural variants with _zero, _one, _other suffixes:
InterpolationThree syntaxes supported universally: {var}, {{var}}, %{var}

How to install the I1n Cli MCP server

```json
{
  "mcpServers": {
    "i1n": {
      "command": "npx",
      "args": ["i1n", "mcp"]
    }
  }
}

Configuration as documented by the project. Restart the client after saving.

Configuration

VariableDescriptionRequired
STORAGE_KEYCredential the server authenticates with.Yes

Example prompts to try

  • Use I1n Cli to Pluralization.
  • Use I1n Cli to Interpolation.

Frequently asked questions

It connects I1n Cli to MCP-compatible AI assistants such as Claude and Cursor, exposing 2 tools (Pluralization, Interpolation) that the assistant can call on your behalf. Instead of copying data back and forth by hand, the assistant works with I1n Cli directly.