API Reference
Hand-written API reference for every Crux package, organized by package.
The reference is organized by package and developer interface. Pick the area you're working with for exact APIs, commands, settings, and protocol behavior.
Developer interfaces
Runtime program and worker
Immutable Runtime programs and the single-owner Node execution worker lifecycle.
VS Code & LSP
Editor installation, workspace trust, binary discovery, settings, diagnostics, navigation, hints, and actions.
Semantic completion
Project Index-aware suggestions for supported Crux dependency slots.
crux CLI & TUI
Local runtime commands, flags, terminal workbench behavior, JSON output, and exit codes.
Packages
@use-crux/core
The base package: prompts, contexts, retrieval, indexing, memory, compaction, agents, flows, plans, tasks, skills, scoring, quality, safety, index, lint, runtime bridge, and observability.
@use-crux/react
Reactive hooks, browser transports, and the SSE server helper for plans, tasks, blackboards, and working memory.
@use-crux/indexer
TypeScript source intelligence worker for the Project Index.
@use-crux/local
The local Crux runtime: crux dev, editor diagnostics through crux lsp, Go services, web devtools hosting, TUI, evals, index, and lint.
@use-crux/postgres
Postgres Runtime Engine store adapter for durable work, events, waiters, timers, leases, outbox rows, and setup checks.
Adapters
@use-crux/ai, @use-crux/anthropic, @use-crux/openai, @use-crux/google, and the adapter interface for custom providers.
Storage
@use-crux/convex, @use-crux/postgres, @use-crux/upstash: RecordStore, SearchStore, and AssetStore adapters.
Plugins
@use-crux/otel: OpenTelemetry integration for production observability.
@use-crux/ingest
Node-first ingestion helpers for text, local files, folders, globs, and URLs.
How reference pages are organized
Package landing pages use package names. Pages inside a package use readable API-area names in the sidebar, while the exact import path appears in the page body.
Every reference page follows the same layout so you can scan quickly:
- Overview: what it is and when to reach for it
- Signature: the TypeScript signature of the export
- Parameters: table of options with types and defaults
- Returns: what comes back
- Example: a minimal working snippet
- Hooks emitted: instrumentation events the export fires (when applicable)
- Related: links to the relevant guide and cookbook recipes
If you want narrative how-to content with "when to use" guidance, look in Guides. For help choosing between browser Devtools, terminal tools, editor integration, and coding-agent docs, start with Developer Tools. If you want full working examples, look in Cookbook. The reference is for what does this function do, exactly.