@stll/chat

Portable React chat primitives: message streams, model selectors, composer action resolution, and observable streaming runtimes.

The host owns authentication, endpoint selection, persistence, provider credentials, translations, and rich-message rendering. It supplies a typed ChatTransport; the package never reads environment variables or silently selects a provider.

import { ChatMessageStream, createChatRuntime } from "@stll/chat";

const runtime = createChatRuntime({ transport });

Validate every explicit provider/model selection with resolveChatModelSelection. It rejects unknown, empty, duplicate, and unconfigured provider/model combinations with ChatConfigurationError.

For TanStack hosts, @stll/chat/durable-transport exports createDurableChatTransport: pass its connection and persistence to ChatClient, call attach() while a viewer is mounted and detach() when it leaves. The host supplies authenticated probe/join URLs and transcript reload callbacks. Resume state comes from the server; this adapter stores no transcript on the device. Network retries rejoin the log with the last event cursor and jittered backoff, bounded to three minutes. Detaching keeps an accepted server turn running; the host must use the turn cancellation endpoint for Stop.