# Docs

Everything an agent or a developer needs to put a sournd engine in a plugin. 111 engines (69 effects and 42 synths), 32 free.

- [For AI agents](/docs/ai/index.md): how an AI coding assistant finds, chooses and integrates an engine. Start here if you are an agent.
- [JUCE quick start](/docs/juce/index.md): add an engine to a JUCE plugin with CMake, three lines.
- [C ABI reference](/docs/abi/index.md): the header, threading and ownership rules, every status code.
- [Licensing](/docs/licensing/index.md): free engines are Apache-2.0; paid engines ship as closed static libraries. No royalty on what you sell.

## How it fits together

```flow
Choose | an engine from the catalogue -> Download | a static library and a C header -> Wire it in | the JUCE module, or the C ABI from any language -> Ship | your plugin or game, yours to sell
```

## Machine-readable

- [llms.txt](/llms.txt): the short guide agents read first.
- [catalog.json](/catalog.json): every engine, its parameters, tier and price.
- [MCP server card](/.well-known/mcp/server-card.json) and the [OpenAPI description](/api/v1/openapi.json).
- [Partners](/partners): verify a plugin binary against the licence watermark.