Elephant-Goldfish Model (EGM) is an open-source plugin for Spec-Driven Development with AI coding agents. Deep-context Elephant sessions draft specifications, and isolated zero-context Goldfish subagents stress-test them before you write code.
| Harness | Install |
|---|---|
| Any AI agent | Ask your agent: Install https://github.com/google/elephant-goldfish-model |
| Antigravity | agy plugin install https://github.com/google/elephant-goldfish-model (or /plugin in IDE) |
| Claude Code | claude plugin marketplace add google/elephant-goldfish-model && claude plugin install egm@egm |
| Codex | codex plugin marketplace add google/elephant-goldfish-model && codex plugin add egm@egm |
| Claude Cowork / ChatGPT | See Harnesses for desktop and workspace setup |
- Ideate & Stress-Test: Run
/egm-brainstormto explore problem boundaries and test early concepts with a Goldfish swarm. - Draft: Run
/egm-draftto convert the concept brief into a living design document underdocs/designs/<feature>.md. - Review & Resolve: Run
/egm-review docs/designs/<feature>.mdto run the multi-stage Goldfish reviewer swarm. - Submit & Implement: Submit the verified design doc via pull request and implement code against the approved specification.
In Claude Code, commands use the /egm: prefix (for example /egm:egm-brainstorm).
For detailed setup guides and walkthroughs, see Getting Started, Harnesses, and Framework Architecture.
| Skill | Command | Description |
|---|---|---|
| Brainstorm | /egm-brainstorm |
Zero-doc ideation tool using a multi-lens Goldfish shootdown swarm to stress-test early concepts. |
| Draft | /egm-draft |
Iterative, section-by-section markdown design specification compiler. |
| Review | /egm-review |
Multi-stage verification pipeline orchestrator (Zoom Out -> Comprehension -> Critic -> Readiness). |
| Review Loop | /egm-review-loop |
Concurrent review subagent dispatch engine supporting direct and hierarchical dispatch. |
| Review Resolve | /egm-resolve |
Interactive triage and automated patch application engine for review findings. |
| Drift Report | /egm-drift-report |
Sequential AST scanner detecting divergence between checked-in specs and live code. |
| Bootstrap | /egm-bootstrap |
Recursive bottom-up codebase documentation generator and sentinel-block upserting engine. |
EGM uses two animal metaphors to structure AI agents across the software development lifecycle:
- 🐘 The Elephant (Remembers Everything): Deep-context agents load system history, architecture diagrams, component boundaries, and user journeys. The Elephant runs structured brainstorming, probes operational limits, and drafts comprehensive specifications.
- 🐠 The Goldfish (Zero-Context Memory): Stateless, isolated subagents read only the draft spec and live source code, without conversational bias. The Goldfish swarm stress-tests designs from conflicting perspectives. Personas in
agents/include Design Critic, Naive Reader, Tech Lead, Codebase Auditor, Structural Validator, Style Editor, and Zoom Out Architect. - 🧑💻 The Human (Owns the Outcomes): AI is an exploration partner and automated auditor, while human engineers own architectural decisions, trade-offs, and final outcomes.
For the foundational essay introducing this methodology, see Dave Rensin's article: Elephants, Goldfish, and the New Golden Age of Software Engineering.
We welcome community contributions! Please review Harnesses and our Contribution Guidelines before submitting pull requests.
Apache 2.0 License applies to this project - see the LICENSE file for details.
This is not an officially supported Google product.
