openground 0.11.1

Ingest official documentation into a local vector database and expose it via MCP for AI coding agents

openground

tldr: openground lets you give controlled access to documentation to AI agents. Everything happens on-device.

openground is an on-device RAG system that extracts documentation from git repos and sitemaps, embeds it for semantic search, and exposes it to AI agents via MCP. It uses a local embedding model, and local lancedb for storing embeddings and for hybrid vector similarity and BM25 full-text search.

Architecture

      ┌─────────────────────────────────────────────────────────────────────┐
      │                           OPENGROUND                                │
      ├─────────────────────────────────────────────────────────────────────┤
      │                                                                     │
      │       SOURCE                  PROCESS              STORAGE/CLIENT   │
      │                                                                     │
      │    ┌──────────┐      ┌───────────┐   ┌──────────┐   ┌──────────┐    │
      │    │ git repo ├─────>│  Extract  ├──>│  Chunk   ├──>│ LanceDB  │    │
      │    |   -or-   |      │ (raw_data)│   │   Text   │   │ (vector  │    │
      │    │ sitemap  │      └───────────┘   └──────────┘   │  +BM25)  │    │
      │    └──────────┘                           │         └────┬─────┘    │
      │                                           ▼              │          │
      │                                    ┌───────────┐         │          │
      │                                    │   Local   |<────────┘          │
      │                                    │ Embedding │         │          │
      │                                    │   Model   │         ▼          │
      │                                    └───────────┘  ┌─────────────┐   │
      │                                                   │ CLI / MCP   │   │
      │                                                   │  (hybrid    │   │
      |                                                   |   search)   |   |
      │                                                   └─────────────┘   │
      │                                                                     │
      └─────────────────────────────────────────────────────────────────────┘

Quick Start

Installation

Recommended to install with uv:

uv tool install openground # Larger package size, automatic GPU/MPS support
uv tool install 'openground[fastembed]' # Lightweight CPU embedding
uv tool install 'openground[fastembed-gpu]' # Experimental CUDA/GPU support through fastembed

or

pip install openground

Add Documentation

Openground can source documentation from git repos or sitemaps.

To add documentation from a git repo to openground, run:

openground add library-name \
  --source https://github.com/example/example.git \
  --docs-path docs/ \
  --version v1.0.0 \
  -y

The --version flag specifies a git tag to checkout (defaults to latest).

To add documentation from a sitemap to openground, run:

openground add library-name \
  --source https://docs.example.com/sitemap.xml \
  --filter-keyword docs/ \
  --filter-keyword blog/ \
  -y

This will download the docs, embed them, and store them into lancedb. All locally.

Multiple versions of the same library can be stored and queried independently.

Sources Files

Openground uses sources.json files to store library source configurations. When you add documentation with --source, openground remembers the source URL so you can add/update the same library later by just specifying its name.

How Sources Files Work

There are two types of sources files:

1. User Sources File (~/.openground/sources.json)

   • Shared across all your projects
   • Created automatically when you first use --source flag
   • This is where new sources are saved by default

2. Project Sources File (.openground/sources.json)

   • Project-specific overrides
   • Created automatically in each project when you add a source
   • Takes priority over user sources when both exist

Priority Order

When looking up a library by name, openground checks:

1. Custom path via --sources-file flag
2. Project-local .openground/sources.json (if exists)
3. User ~/.openground/sources.json (if exists)
4. Package-level bundled sources

Example Workflow

# In project1: Add library with source
cd project1/
openground add fastapi --source https://github.com/tiangolo/fastapi.git --docs-path docs/

# In project2: Same library is now available by name!
cd ../project2/
openground add fastapi  # Finds source from ~/.openground/sources.json

# Project-specific override: Add a different version for this project
echo '{"fastapi": {"type": "git_repo", "repo_url": "https://github.com/tiangolo/fastapi.git", "docs_paths": ["docs"], "languages": ["python"]}}' > .openground/sources.json

Managing Sources

Sources are stored as JSON with this structure:

{
  "fastapi": {
    "type": "git_repo",
    "repo_url": "https://github.com/tiangolo/fastapi",
    "docs_paths": ["docs"],
  },
  "numpy": {
    "type": "sitemap",
    "sitemap_url": "https://numpy.org/doc/sitemap.xml",
    "filter_keywords": ["docs/"]
  }
}

To disable automatic source saving:

openground config set sources.auto_add_local false

Use with AI Agents

To install the MCP server:

# For Cursor
openground install-mcp --cursor

# For Claude Code
openground install-mcp --claude-code

# For OpenCode
openground install-mcp --opencode

# For any other agent
openground install-mcp

Now your AI assistant can search your stored documentation automatically!

Example Workflow

Here's how to add the fastembed documentation and make it available to Claude Code:

# 1. Install openground
uv tool install openground

# 2. Add fastembed to openground
openground add fastembed --source https://github.com/qdrant/fastembed.git --docs-path docs/ --version v0.7.4 -y

# 3. Configure Claude Code to use openground MCP
openground install-mcp --claude-code

# 4. Restart Claude Code
# Now you can ask: "What models are available in fastembed?"
# Claude will search the fastembed docs automatically!

Claude Code Agent

Openground includes a custom Claude Code agent that searches official documentation without polluting your main conversation context. See docs/claude-code-agent.md for installation and usage instructions.

MCP Usage Statistics

To see how many times each tool in the MCP server has been called:

openground stats show # show stats
openground stats clear # reset stats

Development

To contribute or work on openground locally:

git clone https://github.com/poweroutlet2/openground.git
cd openground
uv sync .

License

MIT