Public Universe plugin

Free astronomy tools and seven reusable workflows for Claude Code, Cursor, Codex, ChatGPT, Gemini CLI, GitHub Copilot, Grok and any MCP client. Explore catalogue data, prepare lessons, explain objects and plan an evening of stargazing with Public Universe, a pro bono astronomy service by Wicked Sick Ltd.

• Plugin / package name: publicuniverse (display name: Public Universe)
• MCP server name: publicuniverse
• Repository: https://github.com/Wicked-Sick-Ltd/publicuniverse-plugin (formerly solar-plugin; GitHub redirects the old URL)
• Licence: MIT, © Wicked Sick Limited. Please credit "Wicked Sick Ltd" when you reuse it (see NOTICE).

Remote MCP server

Status: the REST API behind this server is live, but the /mcp endpoint is not yet routed on the production origin (it returns HTTP 404 from the API application, not from Cloudflare). Skills install and load everywhere; live tool calls work once the endpoint is deployed. See the validation record. The planned long-term URL is https://api.publicuniverse.net/mcp; this package will switch only after that host is live.

Install

Pick one route per client: the full plugin (tools + skills) or MCP-only (tools only). Don't install both.

Claude Code

/plugin marketplace add https://github.com/Wicked-Sick-Ltd/publicuniverse-plugin.git
/plugin install publicuniverse@publicuniverse

Or via the Wicked Sick catalogue: /plugin marketplace add Wicked-Sick-Ltd/ai-marketplace then /plugin install publicuniverse@wickedsick. Local checkout: claude --plugin-dir /path/to/publicuniverse-plugin. MCP only:

claude mcp add --transport http publicuniverse https://api.sol.wickedsick.com/mcp

Try /publicuniverse:tonight-sky. Details: docs/clients.md.

Cursor

Install from the Cursor marketplace once listed, or import Wicked-Sick-Ltd/ai-marketplace as a team marketplace. Local: copy this repository to ~/.cursor/plugins/local/publicuniverse/ and reload. MCP only: merge clients/cursor.json into ~/.cursor/mcp.json. Details: docs/clients.md.

Codex (CLI, desktop, IDE)

codex plugin marketplace add Wicked-Sick-Ltd/ai-marketplace --sparse .agents/plugins
codex plugin add publicuniverse@wickedsick

MCP only: codex mcp add publicuniverse --url https://api.sol.wickedsick.com/mcp, or merge clients/codex.toml into ~/.codex/config.toml. Details: docs/openai.md.

ChatGPT

Developer mode → add an MCP connection named Public Universe with the URL above (no auth). Skills are not imported by an MCP connection. Details: docs/openai.md.

Gemini CLI

gemini extensions install https://github.com/Wicked-Sick-Ltd/publicuniverse-plugin

Pin a reviewed release with --ref <tag-or-sha>. Details: docs/clients.md.

GitHub Copilot (CLI and VS Code)

copilot plugin marketplace add Wicked-Sick-Ltd/ai-marketplace
copilot plugin install publicuniverse@wickedsick

VS Code MCP only: merge clients/vscode.json into .vscode/mcp.json. Details: docs/clients.md.

Grok (Grok CLI, grok.com, xAI API)

Grok CLI reads Claude Code marketplaces and plugins, so the Claude route above works as is. Or:

grok plugin install Wicked-Sick-Ltd/publicuniverse-plugin   # full plugin (or a local path)
grok mcp add --transport http publicuniverse https://api.sol.wickedsick.com/mcp   # tools only

On grok.com, add a custom MCP connector with the URL above. Via the xAI API, add {"type": "mcp", "server_url": "https://api.sol.wickedsick.com/mcp", "server_label": "publicuniverse"} to tools. Details: docs/clients.md.

Any other MCP client

Add a remote Streamable HTTP server named publicuniverse with the URL above and no authentication. Most clients accept:

{ "mcpServers": { "publicuniverse": { "type": "http", "url": "https://api.sol.wickedsick.com/mcp" } } }

To use the skills without a plugin system, copy whole folders from skills/ into your client's Agent Skills directory (see docs/clients.md).

Skills

Every skill carries its own reference files, so it can be installed independently. Workflows distinguish unavailable tools from verified results and never invent live values.

Upgrading from solar

• Remove the old solar plugin before enabling publicuniverse.
• The MCP server name changed from solar-system-db to publicuniverse in 0.4.0. Tool names are unchanged, but client prefixes change (for example Claude's mcp__…solar-system-db__get_object becomes mcp__…publicuniverse__get_object); update any saved permission allowlists.
• /solar:… commands are now /publicuniverse:…; solar-data-audit is now publicuniverse-data-audit.

Develop and package

Python 3.11+, no third-party dependencies:

python3 scripts/package.py generate   # regenerate client files from plugin.json + mcp.json
python3 scripts/package.py check
python3 -m unittest discover -s tests -v
python3 scripts/package.py build      # dist/publicuniverse-<version>.zip and .plugin

Edit only root plugin.json (metadata) and mcp.json (connection). generate writes the Claude manifest and marketplace, .mcp.json, gemini-extension.json, the MCP Registry server.json and the clients/ profiles; check rejects drift. See validation and listings.

Data, safety and licence

This is astronomy, not astrology. Keep the source, retrieval date, units, method and limitations with derived answers. These workflows don't control telescopes or certify pointing accuracy. Never look at the Sun through binoculars or a telescope without proper solar filters and supervision.

The plugin is MIT licensed, © 2026 Wicked Sick Limited; please credit "Wicked Sick Ltd" (NOTICE). Catalogue datasets keep their own terms, including credit to NASA/JPL and the IAU Minor Planet Center where applicable.

Built by Wicked Sick Ltd. Feedback: hello@wickedsick.com.