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io.github.scottchronicity/ephemeris-mcp

Precision astronomical ephemeris and planetary positions via the Swiss Ephemeris.

Open source Open in the app JSON README (API)

About

Precision astronomical ephemeris and planetary positions via the Swiss Ephemeris.

Details

Kind
MCP servers
Topic
No topic detected
Publisher
scottchronicity
Origin
official
Category
ferramentas
Transport
local
Version
1.2.0
Stars
4
Forks
2
Open pull requests
1
Last push
2026-03-27T02:25:22Z
Repository state
ativo
Language
Python
License
AGPL-3.0
Added
2026-08-29 04:01:22
Updated
2026-08-29 04:01:22
Origin id
io.github.scottchronicity/ephemeris-mcp

README

# Ephemeris MCP 🌌

[![PyPI version](https://badge.fury.io/py/ephemeris-mcp.svg)](https://badge.fury.io/py/ephemeris-mcp)
[![CI](https://github.com/scottchronicity/ephemeris-mcp/actions/workflows/ci-pr.yml/badge.svg)](https://github.com/scottchronicity/ephemeris-mcp/actions/workflows/ci-pr.yml)
[![License: AGPL v3](https://img.shields.io/badge/License-AGPL_v3-blue.svg)](https://www.gnu.org/licenses/agpl-3.0)

mcp-name: io.github.scottchronicity/ephemeris-mcp

**Precision Astronomical Ephemeris for AI Agents.**

Ephemeris MCP is a Model Context Protocol (MCP) server that provides AI agents with precision planetary positions using the **Swiss Ephemeris**.

To use this in Claude Desktop, add this to your `claude_desktop_config.json`:

```json
"mcpServers": {
  "ephemeris": {
    "command": "uvx",
    "args": ["ephemeris-mcp"]
  }
}
```

## Quick Start

### Install via PyPI (Recommended)

```bash
# Install with uvx (recommended - fast & isolated, no local install needed)
uvx ephemeris-mcp

# Or install globally with pip
pip install ephemeris-mcp
python -m ephemeris_mcp
```

### Register with MCP Clients

Add to your MCP client configuration (client will start server on-demand):

**Claude Desktop** (`~/Library/Application Support/Claude/claude_desktop_config.json`):

```json
{
  "mcpServers": {
    "ephemeris-mcp": {
      "command": "uvx",
      "args": ["ephemeris-mcp"]
    }
  }
}
```

**VS Code/Cursor/Windsurf** (Cline MCP settings):

```json
{
  "mcpServers": {
    "ephemeris-mcp": {
      "command": "uvx",
      "args": ["ephemeris-mcp"]
    }
  }
}
```

The client starts the server process automatically, communicates over stdin/stdout, then terminates it when done.

## Alternative: Docker

If you prefer container isolation:

```bash
# Pull latest image
docker pull ghcr.io/scottchronicity/ephemeris-mcp:latest

# Test it
docker run --rm -i ghcr.io/scottchronicity/ephemeris-mcp:latest
```

Configure MCP client with Docker:

```json
{
  "mcpServers": {
    "ephemeris-mcp": {
      "command": "docker",
      "args": ["run", "--rm", "-i", "ghcr.io/scottchronicity/ephemeris-mcp:latest"]
    }
  }
}
```

## Local Development

```bash
# Clone and install
git clone https://github.com/scottchronicity/ephemeris-mcp.git
cd ephemeris-mcp
uv sync

# Run tests
make test

# Run locally
uv run ephemeris-mcp

# Test the engine directly
make validate-happycase
```

## Available Tools

### `get_planetary_positions`

Returns precise Tropical Zodiac positions for all planets, Sun, Moon, and chart angles.

**Parameters:**

- `iso_time` (string): ISO-8601 timestamp (e.g., `"2025-12-16T15:28:00Z"`)
- `latitude` (float): Observer latitude (default: 42.3314 - Detroit, MI)
- `longitude` (float): Observer longitude (default: -83.0458 - Detroit, MI)

**Returns:**

- `bodies`: Sun, Moon, planets with sign, degrees, motion (direct/retrograde), speed, declination
- `houses`: Ascendant (ASC) and Midheaven (MC) with sign and degrees

## Architecture

See [docs/adr/](docs/adr/) for architectural decisions:

- **ADR 001**: Geocentric Tropical Ecliptic coordinates specification
- **ADR 002**: Semantic versioning with Conventional Commits
- **ADR 003**: CI/CD pipeline architecture

## License

AGPLv3

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