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Explain plugin, skill, command, agent, and hook mechanics used here.
Passed 21 of 21 test cases with the skill, and 7 of 21 without it.
and 24 more in the full report
15 fixed7 passed either way0 still failing0 broke
Tokens, turns and time describe resource use, not a dollar price.
One of 14 test cases the skill fixed. Same model, same prompt, with and without the skill.
What is the relative path from the repository root to the main registry file where all plugins are registered for local installation?
| Checked | Without skill | With skill |
|---|---|---|
| The response identifies .claude-plugin/marketplace.json as the registry file path | Missed | Passed |
The instructions your model reads when the skill loads.
This is the domain pack for how Claude Code plugin machinery works in this
repository. It covers manifests, skills, commands, agents, hooks, and the
marketplace registry, with the local conventions layered on top. Every
contract below was checked against a shipped plugin (mostly plugins/imbue,
plugins/abstract, and plugins/herald) on 2026-07-02 at repo v1.9.15.
When another night-market skill says "see the plugin reference for what a
hook payload is," this is the file it means.
Each term is defined once here and used without redefinition below.
| Term | Meaning in this repo |
|---|---|
| Plugin | A directory under plugins/ shipping skills, commands, agents, and hooks, with its own tests, Makefile, and pyproject.toml. Independently deployable (ADR-0001). |
| Skill | A directory skills/<name>/ containing SKILL.md. Loaded by the model on demand, invoked as Skill(plugin:name). |
| Module | A file under a skill's modules/ subdirectory. Loaded only when the hub SKILL.md routes to it (progressive loading). |
| Command | A markdown file under commands/. Surfaces as a slash command the user types. Repo docs refer to the namespaced form, e.g. /sanctum:sync-capabilities. |
| Agent | A markdown file under agents/ defining a dispatchable subagent: frontmatter plus a system-prompt body. |
| Hook | An executable script Claude Code runs on a lifecycle event, registered in the plugin's hooks/hooks.json. |
| Hook event | The lifecycle point a hook fires on: PreToolUse, PostToolUse, Stop, SessionStart, UserPromptSubmit, and others (full table below). |
| Manifest | .claude-plugin/plugin.json: the file Claude Code reads to register a plugin's components. |
| Marketplace | The root .claude-plugin/marketplace.json registry listing all plugins, installed via /plugin marketplace add. |
| Plugin cache | The directory Claude Code copies installed plugins into and executes them from. It is NOT the repo checkout. |
${CLAUDE_PLUGIN_ROOT} | Placeholder Claude Code expands to the plugin's cache path. The only safe way to reference plugin files from hooks. |
| Host Python | The system Python interpreter that runs hook scripts. Assume 3.9, even though plugin package code targets 3.12. |
Verified tree (imbue, trimmed):
plugins/imbue/
├── .claude-plugin/
│ ├── plugin.json # Claude Code manifest: registers everything
│ └── metadata.json # inter-plugin dependency manifest
├── openpackage.yml # cross-framework export manifest
├── skills/<name>/
test cases passed, vs 7 / 21 without
More skills from the same source and nearby in the registry, with their headline benchmark lift.