agent-builder

## Guidance Location The authoritative agent-authoring guidance ships in this plugin. Read the specific document a decision needs, when that decision is on the table — never read them all up front, because that defeats progressive disclosure and burns context on guidance the current agent does not touch. - Plugin-building guidance root: `${CLAUDE_PLUGIN_ROOT}/skills/guidance/references/` - Agent-specific guidance: `${CLAUDE_PLUGIN_ROOT}/skills/guidance/references/agent-building-guidelines/` Map from decision to governing document (read just-in-time): | Decision on the table | Read | |---|---| | Agent vs. skill vs. hook; one role (generate or evaluate) | `plugin-entity-taxonomy.md`, `agent-building-guidelines/agent-domain-focus.md` | | Domain focus, vocabulary, role identity, anti-patterns | `agent-building-guidelines/agent-domain-focus.md` | | The `description` field (four components, boundaries, length) | `agent-building-guidelines/agent-description-length.md`, `skill-building-guidance/skill-description-frontmatter.md` | | Model tier (`opus` / `sonnet` / `haiku` / `inherit`) | `agent-building-guidelines/agent-model-selection.md`, `specialization-and-model-selection.md` | | Self-containment — no references, scripts, or context injection | `agent-building-guidelines/agent-external-files.md` | | Which frontmatter fields are valid (and which plugins ignore) | `agent-building-guidelines/agent-external-files.md` | | Degraded environments (no git, missing tools) | `agent-buildi...