# Credits

The API uses your SciFig credits: one balance for the website, the API and MCP.

Source: https://scifig.ai/docs/api/credits

## Read the balance

`GET /credits` (scope `credits:read`) returns your balance, the credits reserved by running jobs, your plan and its task limits:

```json
{
  "balance": 2950,
  "reserved": 100,
  "granted_scopes": ["images:generate", "jobs:read", "credits:read"],
  "plan": "plus",
  "plan_level": 2,
  "limits": { "concurrent_tasks": 5, "tasks_per_hour": 200 },
  "top_up_url": "https://scifig.ai/pricing?utm_source=api"
}
```

- `plan` is `free`, `starter`, `plus` or `pro`. An account with a credit-pack balance above zero is treated as `pro` while that balance lasts.
- `tasks_per_hour` is 200 for every plan; `concurrent_tasks` depends on the plan.
- `top_up_url` carries `utm_source=api` for requests sent to the API directly and `utm_source=mcp` for requests made through the MCP server.
- `GET /api/v1/capabilities` requires a valid credential, but no business scope. It returns only `granted_scopes`, never balance, plan or account data.

`GET /pricing` returns every price without authentication; the prices on these pages are read from the same table. There is no separate API plan: buy credits or a subscription on the [pricing page](/pricing).

## Reservation lifecycle

- Creating a job reserves its price atomically; two requests can never spend the same credits.
- Without enough credits the answer is `402 INSUFFICIENT_CREDITS` with `details.top_up_url`: nothing is reserved and nothing runs. The refused request stays in `GET /jobs` as a failed job with that error, and replaying its key returns the same answer.
- A succeeded job is charged its reservation exactly once; a failed or canceled job returns all of it. Internal retries never reserve again, and replaying an `Idempotency-Key` reuses the original reservation.
- Each job reports `credits.reserved`, `credits.charged` and `credits.refunded`, read from the ledger.
- Credits are spent in the same order as on the website: those that expire first are used first, and credits from packs, which do not expire, last.

## cURL

```bash
curl https://scifig.ai/api/v1/credits \
  -H "Authorization: Bearer $SCIFIG_API_KEY"
```

## JavaScript

```javascript
const response = await fetch('https://scifig.ai/api/v1/credits', {
  method: 'GET',
  headers: {
    Authorization: `Bearer ${process.env.SCIFIG_API_KEY}`,
  },
});
const result = await response.json();
console.log(response.status, result);
```

## Python

```python
import os

import requests

headers = {
    "Authorization": f"Bearer {os.environ['SCIFIG_API_KEY']}",
}
response = requests.get(
    "https://scifig.ai/api/v1/credits",
    headers=headers,
    timeout=60,
)
print(response.status_code, response.json())
```