Initial commit: RA-H Open Source Edition

Local-first knowledge management system with BYO API keys.

Features:
- 3-panel UI (Nodes | Focus | Helpers)
- SQLite + sqlite-vec for vector search
- Agent system (Easy/Hard mode orchestrators)
- Content extraction (YouTube, PDF, web)
- Integrate workflow for connection discovery
- Dimension system with auto-assignment

Tech stack:
- Next.js 15 + TypeScript + Tailwind CSS
- Anthropic (Claude) + OpenAI (GPT) via Vercel AI SDK

Setup:
  npm install && npm rebuild better-sqlite3
  scripts/dev/bootstrap-local.sh
  npm run dev

MIT License

docs/1_architecture.md

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+# System Architecture
+
+## Overview
+
+RA-H uses a multi-agent architecture with three specialized AI agents that collaborate to manage your knowledge base. The system is built around **nodes** (knowledge items), **edges** (relationships), and **dimensions** (categories).
+
+## Core Concepts
+
+### Nodes
+Knowledge items stored in the database (papers, ideas, people, projects, videos, tweets, etc). Each node has:
+- **Title** and **content**
+- **Dimensions** (multi-tag categorization)
+- **Metadata** (structured JSON)
+- **Embeddings** (for semantic search)
+- **Links** (for external sources)
+
+### Edges
+Directed relationships between nodes. Edges capture how nodes connect ("relates to", "inspired by", etc).
+
+### Dimensions
+Multi-select categorization tags. Nodes can have multiple dimensions. Some dimensions can be marked as "priority" for focused context.
+
+## Agent Architecture
+
+### Orchestrator Agents (Easy/Hard Mode)
+
+**ra-h-easy (Easy Mode - Default)**
+- **Model:** GPT-5 Mini (`openai/gpt-5-mini`)
+- **Purpose:** Fast, low-latency orchestration for everyday tasks
+- **Caching:** OpenAI implicit caching
+- **Reasoning:** `reasoning_effort: light` for speed
+
+**ra-h (Hard Mode)**
+- **Model:** Claude Sonnet 4.5 (`anthropic/claude-sonnet-4.5`)
+- **Purpose:** Deep reasoning for complex tasks
+- **Caching:** Anthropic explicit prompt caching
+- **Reasoning:** Stronger analytical capabilities
+
+**Tools Available:**
+- `queryNodes`, `queryEdge`, `searchContentEmbeddings`
+- `webSearch`, `think`
+- `executeWorkflow` (delegates to wise-rah)
+- `createNode`, `updateNode`, `createEdge`, `updateEdge`
+- `youtubeExtract`, `websiteExtract`, `paperExtract`
+
+**Mode Switching:**
+Users toggle via UI (⚡ Easy / 🔥 Hard). Choice persists in localStorage. **Seamless mid-conversation switching** - context maintained across mode changes.
+
+### Wise RA-H (Workflow Executor)
+
+**wise-rah**
+- **Model:** GPT-5 (`openai/gpt-5`)
+- **Purpose:** Executes predefined workflows (integrate, deep analysis)
+- **Direct write access:** Calls `updateNode` directly (no delegation)
+- **Context isolation:** Returns summaries only to orchestrator
+
+**Tools Available:**
+- `queryNodes`, `getNodesById`, `queryEdge`, `searchContentEmbeddings`
+- `webSearch`, `think`
+- `updateNode` (append-only, enforced at tool level)
+
+**Key Workflows:**
+- **Integrate:** Database-wide connection discovery (5-step: plan → ground → search → contextualize → append)
+
+### Mini RA-H (Delegate Workers)
+
+**mini-rah**
+- **Model:** GPT-4o Mini (`openai/gpt-4o-mini`)
+- **Purpose:** Spawned for write operations, extraction, batch tasks
+- **Execution:** Isolated context, returns summaries only
+
+**Tools Available:**
+- All read tools + `createNode`, `updateNode`, `createEdge`, `updateEdge`
+- Extraction tools (`youtubeExtract`, `websiteExtract`, `paperExtract`)
+
+## Prompt Caching
+
+**Anthropic (Claude):**
+- Explicit cache control blocks in system prompts
+- Caches tool definitions, workflows, base context
+
+**OpenAI (GPT-5/4o):**
+- Implicit caching based on prefix matching
+- Optimized prompts for cache reuse
+- `reasoning_effort` parameter for speed/quality tradeoff
+
+## Context Hygiene
+
+**Orchestrator:**
+- Maintains full conversation history
+- Sees pinned nodes + focused node
+- Delegates isolation ensures clean context
+
+**Workers (wise-rah/mini-rah):**
+- Execute in isolated sessions
+- Return structured summaries only
+- Do NOT pollute orchestrator context with tool execution details
+
+## UI Integration
+
+Users interact with a single interface that automatically routes requests to the appropriate agent based on:
+- **Mode selection** (Easy/Hard)
+- **Workflow triggers** (executeWorkflow → wise-rah)
+- **Delegation needs** (mini-rah spawned in background)
+
+All agents share the same **pinned context** (up to 10 nodes) plus the **focused node** for consistent knowledge access.