# SDK quickstart

> Connect an existing x402 service to Forge.

Source: https://docs.forgeintel.co/sdk/quickstart

Create a service in Forge and an API key on its **Activity** page (**Set up API key**). Set `FORGE_API_KEY` on the server. Keep it out of source control and browser code. Use your existing x402 payment middleware and routes.

  #### Node.js · Express

Requires Node.js 20.19+ and Express 4.21 or 5.

```js server.js
import express from "express"
import { createForge } from "@forgeintel/sdk"

const app = express()
const forge = createForge({
  apiKey: process.env.FORGE_API_KEY,
  agentContext: true, // ask agents who they are, optional; off by default
})

app.use(forge.middleware()) // before your existing x402 middleware
// Keep your existing payment middleware, OpenAPI route, and handlers.
```

Install: `npm install @forgeintel/sdk@0.5.0-beta.17`.

Both switches are off by default: with only an API key, Forge reports telemetry and changes nothing agents see. With `agentContext: true`, Forge asks agents for their name and search query and records them when sent, but never rejects a paid call without them; `{ required: true }` requires them. [Express details](https://docs.forgeintel.co/integrations/express).

  #### Python · FastAPI

Requires Python 3.10+ and an ASGI application.

```python server.py
import os
from fastapi import FastAPI
from forgeintel import Forge, ForgeMiddleware

app = FastAPI()
# Add your existing x402 middleware and routes first.
forge = Forge(
    api_key=os.environ["FORGE_API_KEY"],
    agent_context=True,  # ask agents who they are, optional; off by default
)
app.add_middleware(ForgeMiddleware, forge=forge)
```

Install: `python -m pip install forgeintel-sdk==0.1.0b14`.

Starlette runs the last added middleware first, so Forge goes outside payment handling. Keep serving `server:app`. [Python details](https://docs.forgeintel.co/integrations/python).

> Prefer to start from working code? [forge-examples](https://github.com/tryforgeintel/forge-examples) has the same paid weather API in Express and FastAPI, with Forge already wired in.

## Check the connection

Confirm the SDK's diagnostics report `enabled: true` with no configuration errors. Deploy, make an unpaid request to an existing paid route, wait for the background event queue to flush, then select **Test connection** on the service's **Activity** page. This confirms collector contact; it does not prove service ownership or a completed payment. [Verification steps](https://docs.forgeintel.co/guides/verify).