# LeanKG - AI Agent Context

## Project Overview

LeanKG is a lightweight knowledge graph for codebase understanding. It indexes code, builds dependency graphs, calculates impact radius, and exposes everything via MCP for AI tool integration.

**Tech Stack:** Rust + CozoDB + tree-sitter + MCP

## Quick Start

```bash
# Index a codebase
cargo run -- init
cargo run -- index ./src

# Calculate impact radius
cargo run -- impact src/main.rs 3

# Start MCP server
cargo run -- serve
```

## Development Workflow

**When implementing features, follow:** `docs/workflow-opencode-agent.md`

### Pattern: Update Docs → Implement → Test → Commit → Push

1. **Update docs first** - PRD (`docs/requirement/prd-leankg.md`) → HLD (`docs/design/hld-leankg.md`) → README
2. **Implement** - Follow patterns in `docs/workflow-opencode-agent.md`
3. **Build & test** - `cargo build && cargo test`
4. **Commit** - `git commit -m "feat: description"` (one feature per commit)
5. **Push** - `git pull --rebase && git push`

## Key Commands

```bash
cargo build      # Build project
cargo test       # Run tests
cargo run -- <cmd>  # Run CLI commands
```

## Important Files

| File | Purpose |
|------|---------|
| `src/lib.rs` | Module exports |
| `src/db/models.rs` | Data models (CodeElement, Relationship, BusinessLogic) |
| `src/graph/query.rs` | Graph query engine |
| `src/mcp/tools.rs` | MCP tool definitions |
| `src/mcp/handler.rs` | MCP tool handlers |
| `src/indexer/extractor.rs` | Code parsing with tree-sitter |

## Data Model

- **CodeElement** - Files, functions, classes with `qualified_name` (e.g., `src/main.rs::main`)
- **Relationship** - `imports`, `calls`, `tested_by`, `references`, `documented_by`
- **BusinessLogic** - Annotations linking code to business requirements

## MCP Tools

Core tools: `query_file`, `get_dependencies`, `get_dependents`, `get_impact_radius`, `get_review_context`, `find_function`, `get_call_graph`, `search_code`, `generate_doc`, `find_large_functions`, `get_tested_by`

Doc/Traceability tools: `get_doc_for_file`, `get_files_for_doc`, `get_doc_structure`, `get_traceability`, `search_by_requirement`, `get_doc_tree`, `get_code_tree`, `find_related_docs`

## Verification Status

See `docs/implementation-feature-verification-2026-03-25.md` for test results.

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*Last updated: 2026-03-25*
