> ## Documentation Index
> Fetch the complete documentation index at: https://ag-ae4b3bf7.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Quickstart

> Check payment status and run a full refund flow in under 5 minutes

Prereq: credentials set per [Installation](/installation).

## Check payment status

Ask your MCP-capable agent:

> Is payment #12345 paid?

Under the hood:

```python theme={null}
from robokassa import RobokassaClient

async with RobokassaClient("my-shop", password2="...") as client:
    state = await client.check_payment(inv_id=12345)
    print(state.is_paid, state.state_code, state.info.op_key)
```

## Full refund flow

```python theme={null}
from robokassa import RobokassaClient

async with RobokassaClient("my-shop", password2="p2", password3="p3") as client:
    # 1. Read the operation's OpKey.
    state = await client.check_payment(12345)
    assert state.info.op_key, "payment not completed yet"

    # 2. Initiate refund.
    created = await client.refund_create(state.info.op_key)
    print("refund requestId:", created.request_id)

    # 3. Poll until terminal.
    import asyncio
    while True:
        status = await client.refund_status(created.request_id)
        if status.is_terminal:
            print("final state:", status.state)
            break
        await asyncio.sleep(10)
```

## Verify a ResultURL webhook (FastAPI)

```python theme={null}
from fastapi import FastAPI, Request, HTTPException
from fastapi.responses import PlainTextResponse
from robokassa import verify_result_signature, build_ok_response

app = FastAPI()

@app.post("/robokassa/result")
async def result_url(req: Request) -> PlainTextResponse:
    form = dict(await req.form())
    if not verify_result_signature(form, password2="..."):
        raise HTTPException(status_code=403, detail="Bad signature")
    # Persist, mark invoice as paid, etc.
    return PlainTextResponse(build_ok_response(form["InvId"]))
```

Next: [MCP Tools →](/tools)