# Caspian Docs

> You write `onMessage` / `on_message` and `thread.post`. Caspian desugars that into an inspectable list of rules. Same program: test, self-host, or hosted gateway. Package: `caspian`.

Source of truth: the Caspian SDK — Python `caspian`, TypeScript `caspian`, CLI `caspian`.

## Getting started
- [Introduction](https://trycaspianai.com/docs/index.html): Caspian(), hosted vs self-host, adapters.
- [Quickstart](https://trycaspianai.com/docs/quickstart.html): Telegram handlers once; bot.py webhook or hosted.py run().
- [Core concepts](https://trycaspianai.com/docs/concepts.html): App/rules, thread, overlap, three POSTs.

## Usage
- [Sending & receiving](https://trycaspianai.com/docs/messaging.html): thread.post / send / reply / typing / edit / react.
- [Handling events](https://trycaspianai.com/docs/handling-events.html): on_message, on_action, command, overlap, skipped.
- [Overlap](https://trycaspianai.com/docs/overlap.html): queue / debounce / drop / parallel / stream, bound, ctx.skipped, adapter keys.
- [Streaming](https://trycaspianai.com/docs/streaming.html): thread.stream() post-then-edit.
- [Hosted & self-host](https://trycaspianai.com/docs/serverless.html): handle, poll, listen, run.

## Channels (catalog)
- [Overview](https://trycaspianai.com/docs/channels.html)
- Telegram (webhook/poll, BotFather always), Slack (listen socket), Discord (listen socket), Email, WhatsApp, Messenger, SMS, Voice, iMessage, X, Linear.

## Platform
- [Authentication](https://trycaspianai.com/docs/authentication.html): self-host needs no key; hosted CASPIAN_API_KEY; caspian init / login.
- [Webhooks](https://trycaspianai.com/docs/webhooks.html): provisioning vs platform vs event delivery.
- [CLI](https://trycaspianai.com/docs/domains.html): channels add, catalog, call, threads.
- [Tools](https://trycaspianai.com/docs/behavior-guides.html): cx.tools(preset=messenger|outbound).

## SDK reference
- [Python](https://trycaspianai.com/docs/sdk-python.html): Caspian, Thread, on_message, handle / poll / listen / run.
- [TypeScript](https://trycaspianai.com/docs/sdk-js.html): Caspian, onMessage, adapters at caspian/telegram, …
- [REST](https://trycaspianai.com/docs/api-rest.html): hosted /v1/* the SDK already speaks.