# SFXForge AI developers: REST API, OpenAPI and MCP server

SFXForge AI generates game sound effects from text prompts. Besides the Unity plugin and the web version, AI agents, scripts and CI pipelines can use it through an MCP server and a REST API, with the same credits, prices and sound library as your account.

- **API reference**: [https://api.sfxforgeai.com/api/docs](https://api.sfxforgeai.com/api/docs)
- **OpenAPI document**: [https://api.sfxforgeai.com/api/docs/openapi.json](https://api.sfxforgeai.com/api/docs/openapi.json)
- **MCP server**: `https://api.sfxforgeai.com/api/mcp` (Streamable HTTP)
- **For AI agents**: [llms.txt](https://sfxforgeai.com/llms.txt)

## Authentication

Create an API key in the [dashboard](https://sfxforgeai.com/dashboard/#api-keys) under **API keys** and send it as a bearer token:

```
Authorization: Bearer sfx_…
```

A key is shown only once, when it's created. Keys can expire after 30, 90 or 365 days, or last until you revoke them. Requests with an unknown, revoked or expired key return `401`; routes a key can't use return `403`.

## MCP server

Coding agents connect to `https://api.sfxforgeai.com/api/mcp` with an API key, and can then generate, list, download, move and delete sounds, manage folders, and check credits.

### Claude Code

```
claude mcp add --transport http sfxforge https://api.sfxforgeai.com/api/mcp --header "Authorization: Bearer sfx_…"
```

### Codex

Put the key in the `SFXFORGE_API_KEY` environment variable, then:

```
codex mcp add sfxforge --url https://api.sfxforgeai.com/api/mcp --bearer-token-env-var SFXFORGE_API_KEY
```

### Other MCP clients

Connect over Streamable HTTP and send the key in an `Authorization: Bearer sfx_…` header.

### Tools

| Tool | What it does |
| --- | --- |
| `generate_sound_effect` | Generates a sound from a prompt (1–60 whole seconds, one-shot or loop, MP3 or WAV) and returns a download URL |
| `list_sounds`, `get_download_url` | Find sounds in the library and get a fresh download URL |
| `move_sound`, `delete_sound` | Organize or remove sounds |
| `list_folders`, `create_folder`, `rename_folder`, `move_folder`, `delete_folder` | Manage folders |
| `get_credit_balance`, `get_credit_history` | Check credits and the key's 24-hour limit |

## REST API

Every route an API key can call is in the [API reference](https://api.sfxforgeai.com/api/docs). For example, to generate a two-second sound:

```
curl https://api.sfxforgeai.com/api/generations/generate \
  -H "Authorization: Bearer $SFXFORGE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"data": {"prompt": "sword clash with a metallic ring", "durationSeconds": 2}}'
```

Then get a download URL with `GET /api/generations/{id}/download`. Download URLs expire, so save the file right away or ask for a new URL later.

## Credits and limits

Every generation spends 10 credits per second of audio from your balance. Check it with `GET /api/credits/balance`. A key can also have a limit of credits per rolling 24 hours, set in the dashboard: a generation that would go over it returns `429`. Generating needs the latest [Terms](https://sfxforgeai.com/terms/) to be accepted on the website once.

## Help

Questions about the API or the MCP server: [support@sfxforgeai.com](mailto:support@sfxforgeai.com).