Spec-driven development plugin for Claude Code.
Markdown specs capture intent. Code is a downstream manifestation of spec intent. The relationship is bidirectional: specs shape code, code can update specs, and conflicts become human decisions.
Development intent lives in chat messages, commit messages, and the developer's head. When an AI starts a new session, it sees code but not the reasoning behind it.
Eidos keeps intent in spec files alongside the code. Specs describe what a system should be. When spec and code drift apart, neither automatically wins — the human decides which to update.
project/ eidos/ # what it SHOULD be (specs, claims) memory/ # how we got here (plans, decisions, sessions) src/ # what it IS (code) Specs describe timeless intent. Plans describe time-bound work. Code is the result.
Write a spec to capture what you want — behaviour, design, verification. This can be manual or collaborative (/eidos:spec walks you through it).
Then push it into code:
/eidos:push my-feature-spec Verify — with tests, manually, or both. If something's off, update the spec, commit, push again. /eidos:push recent 1 picks up the latest spec change and its precise diff. Repeat.
You already have the manifestation — mine it for intent:
/eidos:pull the auth module Review the extracted spec, refine it, and iterate from there. Now you have a spec to push against, drift-check, and evolve.
Multi-step work gets a plan:
/eidos:plan migrate the database layer Plans live in memory/, persist across sessions, and track progress phase by phase. Resume with /eidos:plan-continue.
Other procedural skills accumulate context the same way:
/eidos:research— investigate external topics, document findings with sources/eidos:observe— capture testing issues mid-plan, update specs, inject tasks/eidos:decision— record architectural choices with options and rationale
AI "learning on the job" is just capturing ephemeral knowledge into files and composing them into session context.
That knowledge can be anywhere — your chat history, a coworker's head, legacy code nobody dares touch. Eidos gives it all a place to land and a way to get loaded when it matters.
Requires Claude Code.
# Add marketplace /plugin marketplace add agenticnotetaking/eidos # Install plugin /plugin install eidos@eidosThen restart Claude and run /eidos:init inside any project to bootstrap the folder structure.
Run /eidos:help for the full list. Highlights by category:
Core loop — sync between spec and code:
| Skill | What it does |
|---|---|
/eidos:spec | Create a spec via structured Q&A |
/eidos:push | Implement code to match a spec |
/eidos:pull | Reverse-engineer a spec from existing code |
/eidos:drift | Analyse divergence between specs and code |
/eidos:sync | Bidirectional reconciliation |
/eidos:coherence | Check specs against each other for contradictions |
/eidos:weave | Discover missing wiki links, prune stale ones |
Planning — structured multi-step work:
| Skill | What it does |
|---|---|
/eidos:plan | Plan multi-step work with phases and actions |
/eidos:plan-continue | Resume work on an existing plan |
/eidos:research | Research a topic and document findings |
/eidos:decision | Record a decision with options and rationale |
/eidos:brainstorm | Explore ideas around a topic |
/eidos:experiment | Log-based iterative exploration |
Observation — understand what you have:
| Skill | What it does |
|---|---|
/eidos:observe | Capture testing issues mid-plan |
/eidos:architecture | Snapshot codebase structure |
/eidos:code-review | Review code for quality and security |
/eidos:reflect | Extract learnings from a session or file |
Utility — workflow glue:
| Skill | What it does |
|---|---|
/eidos:todo | Create quick task files |
/eidos:done | End session with export and merge offer |
/eidos:annotate | Leave inline AI feedback for human review |
/eidos:toclaude | Persist behaviour corrections to CLAUDE.md |
/eidos:toeidos | Route insights into specs and claims |
Eidos (εἶδος) — ancient Greek for "form" or "ideal form".
For Plato, eidos is the ideal that exists prior to any instance. /push is Platonic: start with the ideal, make it real. For Aristotle, eidos is the essence within particular things — discovered by studying concrete instances. /pull is Aristotelian: start with code, extract intent. The loop between them — spec meets reality, reality pushes back, spec evolves — is dialectical refinement.
MIT