# Upjack

> Upjack is a declarative framework for building AI-powered applications.
> The fastest way to start is with the app-builder skill: install it with
> `npx @nimblebrain/mpak skill install @nimblebraininc/upjack-app-builder`, describe the app
> you want, and your agent generates everything. You can also build by hand
> using JSON Schema and Markdown. Either way, Upjack provides entity
> management, validation, search, and a complete MCP server — automatically.

Upjack is built by NimbleBrain (https://nimblebrain.ai).

## Documentation

- [Introduction](https://upjack.dev/introduction/): What Upjack is and key concepts
- [Quick Start](https://upjack.dev/quick-start/): Install, scaffold, and run in 5 minutes
- [Architecture](https://upjack.dev/concepts/architecture/): Design philosophy and runtime architecture
- [Thesis](https://upjack.dev/concepts/thesis/): Why AI-native apps need a new framework
- [Three Tiers](https://upjack.dev/concepts/three-tiers/): Complexity levels from no-code to custom server
- [Manifest Reference](https://upjack.dev/reference/manifest/): Complete manifest format specification
- [Schemas](https://upjack.dev/reference/schemas/): Published JSON Schemas, hosted URLs, and validation
- [Entity Model](https://upjack.dev/reference/entity-model/): Base schema, IDs, storage, lifecycle
- [Runtime Tools](https://upjack.dev/reference/runtime-tools/): 6 CRUD operations and their interfaces
- [Bundles & Skills](https://upjack.dev/reference/bundles-and-skills/): Dependencies and domain expertise
- [Lifecycle](https://upjack.dev/reference/lifecycle/): Install, update, uninstall operations
- [Python Library](https://upjack.dev/libraries/python/): upjack PyPI package
- [TypeScript Library](https://upjack.dev/libraries/typescript/): @nimblebrain/upjack npm package

## Examples

- [CRM](https://upjack.dev/examples/crm/): Full-featured CRM with 5 entities, skills, bundles
- [Todo](https://upjack.dev/examples/todo/): Mid-complexity todo with hooks, schedules, views
- [Research Assistant](https://upjack.dev/examples/research-assistant/): Minimal 4-entity example

## Key Facts

- License: Apache 2.0
- Python package: upjack (PyPI)
- TypeScript package: @nimblebrain/upjack (npm)
- Source: https://github.com/NimbleBrainInc/upjack
- Generates MCP tools per entity (create, get, update, list, search, delete, plus graph traversal). Entity `tools` array controls which appear in tools/list; all remain callable
- Uses JSON Schema (draft 2020-12) for entity definitions
- Storage: git-backed JSON files
- Entity IDs: type-prefixed ULIDs (e.g., ct_01HZ3QKB...)