Skip to main content Configure Mistral AI local development with hot reload and testing.
Use when setting up a development environment, configuring test workflows,
or establishing a fast iteration cycle with Mistral AI.
Trigger with phrases like "mistral dev setup", "mistral local development",
"mistral dev environment", "develop with mistral".
npx skills add jeremylongshore/claude-code-plugins-plus-skills --skill mistral-local-dev-loop ai automation claude-code devops mcp ai-agents
Mistral AI Local Dev Loop
Overview
Set up a fast, reproducible local development workflow for Mistral AI integrations: project scaffold, environment config, hot reload with tsx, unit tests with Vitest mocking, and integration tests against the live API.
Prerequisites
Completed mistral-install-auth setup
Node.js 18+ with npm/pnpm
MISTRAL_API_KEY set in environment
Instructions
Step 1: Project Structure
my-mistral-project/
├── src/
│ ├── mistral/
│ │ ├── client.ts # Singleton client
│ │ ├── config.ts # Config with Zod validation
│ │ └── types.ts # TypeScript types
│ └── index.ts
├── tests/
│ ├── unit/
│ │ └── mistral.test.ts
│ └── integration/
│ └── mistral.integration.test.ts
├── .env.local # Local secrets (git-ignored)
├── .env.example # Template for team
├── tsconfig.json
├── vitest.config.ts
└── package.json
Step 2: Package Configuration
package.json
{
"type": "module",
"scripts": {
"dev": "tsx watch src/index.ts",
"build": "tsc",
"test": "vitest run",
"test:watch": "vitest",
"test:integration": "vitest run tests/integration/",
"typecheck": "tsc --noEmit"
},
"dependencies": {
"@mistralai/mistralai": "^1.0.0"
},
"devDependencies": {
"@types/node": "^20.0.0",
"dotenv": "^16.0.0",
"tsx": "^4.0.0",
"typescript": "^5.0.0",
"vitest": "^1.0.0"
}
}
{
"compilerOptions": {
"target": "ES2022",
"module": "NodeNext",
"moduleResolution": "NodeNext",
"strict": true,
"esModuleInterop": true,
"skipLibCheck": true,
"outDir": "dist",
"rootDir": "src"
},
"include": ["src/**/*"],
"exclude": ["node_modules", "dist"]
}
Step 3: Environment Setup # Create environment template
cat > .env.example << 'EOF'
MISTRAL_API_KEY=your-api-key-here
MISTRAL_MODEL=mistral-small-latest
LOG_LEVEL=debug
EOF
cp .env.example .env.local
echo '.env.local' >> .gitignore
echo '.env' >> .gitignore
Step 4: Client Module // src/mistral/client.ts
import { Mistral } from '@mistralai/mistralai';
import 'dotenv/config';
let instance: Mistral | null = null;
export function getMistralClient(): Mistral {
if (!instance) {
const apiKey = process.env.MISTRAL_API_KEY;
if (!apiKey) throw new Error('MISTRAL_API_KEY not set');
instance = new Mistral({ apiKey, timeoutMs: 30_000 });
}
return instance;
}
export function resetClient(): void {
instance = null;
}
Step 5: Unit Tests with Mocking import { defineConfig } from 'vitest/config';
export default defineConfig({
test: {
globals: true,
environment: 'node',
include: ['tests/**/*.test.ts'],
coverage: { provider: 'v8', reporter: ['text', 'json'] },
},
});
tests/unit/mistral.test.ts
import { describe, it, expect, vi, beforeEach } from 'vitest';
// Mock the entire SDK
vi.mock('@mistralai/mistralai', () => ({
Mistral: vi.fn().mockImplementation(() => ({
chat: {
complete: vi.fn().mockResolvedValue({
id: 'test-id',
model: 'mistral-small-latest',
choices: [{
index: 0,
message: { role: 'assistant', content: 'Mocked response' },
finishReason: 'stop',
}],
usage: { promptTokens: 10, completionTokens: 5, totalTokens: 15 },
}),
stream: vi.fn().mockImplementation(async function* () {
yield { data: { choices: [{ delta: { content: 'Streamed ' } }] } };
yield { data: { choices: [{ delta: { content: 'response' } }] } };
}),
},
embeddings: {
create: vi.fn().mockResolvedValue({
data: [{ embedding: new Array(1024).fill(0.1) }],
usage: { totalTokens: 5 },
}),
},
models: {
list: vi.fn().mockResolvedValue({ data: [{ id: 'mistral-small-latest' }] }),
},
})),
}));
describe('Mistral Client', () => {
beforeEach(() => { vi.clearAllMocks(); });
it('should complete chat', async () => {
const { Mistral } = await import('@mistralai/mistralai');
const client = new Mistral({ apiKey: 'test' });
const response = await client.chat.complete({
model: 'mistral-small-latest',
messages: [{ role: 'user', content: 'Test' }],
});
expect(response.choices?.[0]?.message?.content).toBe('Mocked response');
expect(response.usage?.totalTokens).toBe(15);
});
it('should generate embeddings', async () => {
const { Mistral } = await import('@mistralai/mistralai');
const client = new Mistral({ apiKey: 'test' });
const response = await client.embeddings.create({
model: 'mistral-embed',
inputs: ['test text'],
});
expect(response.data[0].embedding).toHaveLength(1024);
});
});
Step 6: Integration Test (Live API) // tests/integration/mistral.integration.test.ts
import { describe, it, expect } from 'vitest';
import { Mistral } from '@mistralai/mistralai';
const apiKey = process.env.MISTRAL_API_KEY;
describe.skipIf(!apiKey)('Mistral Integration', () => {
const client = new Mistral({ apiKey: apiKey! });
it('should list models', async () => {
const models = await client.models.list();
expect(models.data?.length).toBeGreaterThan(0);
}, 10_000);
it('should complete chat', async () => {
const response = await client.chat.complete({
model: 'mistral-small-latest',
messages: [{ role: 'user', content: 'Reply with "ok"' }],
maxTokens: 10,
temperature: 0,
});
expect(response.choices?.[0]?.message?.content).toBeTruthy();
}, 15_000);
it('should generate embeddings', async () => {
const response = await client.embeddings.create({
model: 'mistral-embed',
inputs: ['test'],
});
expect(response.data[0].embedding).toHaveLength(1024);
}, 10_000);
});
Output
Working dev environment with hot reload (tsx watch)
Unit tests with full SDK mocking
Integration tests against live API (skip when no key)
Environment variable management with .env.local
Error Handling Error Cause Solution Module not found Missing dependency Run npm install Env not loaded Missing .env.local Copy from .env.example Integration timeout Slow API response Increase test timeout Mock type errors SDK interface changed Update mock to match current SDK
Resources
Next Steps See mistral-sdk-patterns for production-ready code patterns.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Search for places (restaurants, cafes, etc.) via Google Places API proxy on localhost.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Search for places (restaurants, cafes, etc.) via Google Places API proxy on localhost.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.