Mistral Ai

Mistral AI MCP server + CLI. OCR documents, TTS text-to-speech, STT speech-to-text via Voxtral.

Features

• OCR - Extract text from PDFs, DOCX, PPTX, XLSX, images
• TTS - Generate speech with preset voices or voice cloning
• STT - Transcribe audio (batch or realtime)

Install

npm install -g mistral-ai-mcp

Requires Node.js 18+.

CLI Usage

mistral-ai ocr <file-or-url>    # Extract text from documents/images
mistral-ai tts <text>            # Generate speech from text
mistral-ai stt <audio>           # Transcribe audio to text
mistral-ai config ...            # Manage configuration

OCR Examples

# Local PDF
mistral-ai ocr ./document.pdf > output.md

# From URL
mistral-ai ocr https://arxiv.org/pdf/2301.00001.pdf > paper.md

# Tables
mistral-ai ocr ./document.pdf --table-format html

TTS Examples

# Preset voice
mistral-ai tts "Hello, world!" --voice-id alice

# Voice cloning via reference audio
mistral-ai tts "Hello from me!" --ref-audio ./my-voice.wav

# Output format
mistral-ai tts "Hello!" --voice-id bob --format wav > output.wav

STT Examples

# Basic transcription
mistral-ai stt ./audio.mp3

# Realtime mode (low latency)
mistral-ai stt ./audio.mp3 --realtime

# Speaker diarization
mistral-ai stt ./meeting.mp3 --diarize

# Specific language
mistral-ai stt ./audio.mp3 --language en

Supported Formats

Tool	Input Formats	Output Formats
OCR	PDF, DOCX, PPTX, XLSX, PNG, JPEG, AVIF	Markdown + YAML
TTS	Text	MP3, WAV, PCM, FLAC, Opus
STT	MP3, WAV, FLAC, OGG, WebM	Text + JSON

Configuration

Set API Key

mistral-ai config api_key <your-key>

Or via environment:

export MISTRAL_API_KEY=your-key

Config Location

• Linux/macOS: ~/.mistral-ai/config.json
• Windows: %USERPROFILE%\.mistral-ai\config.json

Override with MISTRAL_AI_CONFIG_DIR env var.

Show Config

mistral-ai config show

Config Options

mistral-ai config api_key <key>    # Set API key
mistral-ai config base_url <url>    # API endpoint (default: https://api.mistral.ai/v1)
mistral-ai config model <model>     # Default OCR model

MCP Server

Start server with stdio transport:

mistral-ai-mcp

MCP Tools

Tool	Description
ocr_pdf	Extract text from PDF sources
tts_speech	Generate speech from text
stt_transcribe	Transcribe audio to text

Example (Node.js client)

import { StdioClientTransport } from '@modelcontextprotocol/sdk/client/stdio.js';
import { Client } from '@modelcontextprotocol/sdk/client/index.js';

const transport = new StdioClientTransport({
  command: 'node',
  args: ['node_modules/.bin/mistral-ai-mcp'],
  env: { MISTRAL_API_KEY: 'your-key' },
});

const client = new Client({ name: 'test', version: '1.0.0' }, { capabilities: {} });
await client.connect(transport);

// OCR
const ocrResult = await client.callTool({
  name: 'ocr_pdf_url',
  arguments: { pdf_url: 'https://example.com/doc.pdf' },
});

// TTS
const ttsResult = await client.callTool({
  name: 'tts_speech',
  arguments: { text: 'Hello!', voice_id: 'alice' },
});

// STT
const sttResult = await client.callTool({
  name: 'stt_transcribe',
  arguments: { audio_source: './audio.mp3' },
});

Development

Setup

npm install

Scripts

npm run dev          # Run with tsx (watch mode)
npm run build        # Compile TypeScript
npm run clean        # Remove dist/
npm run lint         # ESLint check
npm run format       # Prettier check
npm run format:write # Prettier fix
npm run typecheck    # Type check only
npm run test         # Run tests

Git Hooks

Husky hooks enforce code quality:

• pre-commit: Runs npm run lint && npm run format
• pre-push: Runs npm run typecheck && npm run test

CI/CD

GitHub Actions workflows:

• CI (.github/workflows/ci.yml): Lint, build, typecheck on push/PR
• Tests (.github/workflows/test.yml): Run tests on push/PR

License

ISC