Plugin Model

Stargraph uses a two-stage plugin loader built on importlib.metadata entry points and pluggy hooks. Distributions register under one of four groups: stargraph.tools, stargraph.skills, stargraph.stores, or stargraph.packs. Each distribution exposes a single stargraph_plugin() callable plus a stdlib-only PluginManifest so Stargraph can check api_version before importing the module.

Why two stages

• Discovery without import. Entry points are enumerated, not loaded — startup stays cheap.
• Compatibility gating. Manifests are read from the dist-info; an incompatible plugin never imports.
• Hook composition. Once gated, pluggy registers the module and composes hooks deterministically.

Reference

• PluginManifest schema, entry-point groups, two-stage loader
• Hookspec catalog (collect-all vs firstresult, full signatures)
• Skills (Skill model, ReactSkill, salience, refs)