google/elephant-goldfish-model

What is it?

Key features

• 01Drafts design specifications with a context-rich agent, pausing for feedback after each section.
• 02Runs reviews with fresh subagents that see only the document and referenced source material.
• 03Covers five review stages, checking design, clarity, code fit and implementation plan.
• 04Includes a drift report that compares checked-in documents with current source code.
• 05Works with Antigravity, Claude Code and Codex through their plugin systems.

Use cases

• Designing a feature that needs architectural decisions before any code is written.
• Stress-testing a spec for hidden assumptions before handing it to a coding agent.
• Writing documentation for an existing codebase and checking it for drift over time.

Quick start

1. 1

   Add the plugin marketplace in Claude Code

   claude plugin marketplace add google/elephant-goldfish-model
2. 2

   Install the EGM plugin

   claude plugin install egm@egm
3. 3

   Start a new session, then run the brainstorm skill on a feature that needs design decisions

   /egm:egm-brainstorm

Things to know

• !Goldfish reviews require an agent that can create fresh subagent contexts; otherwise EGM stops the review.
• !A review does not replace tests or human judgment, and EGM is not an officially supported Google product.

In collections

Topics

FAQ

What is elephant-goldfish-model?

An open-source agent plugin for designing software: an agent drafts specs, then fresh zero-context subagents review them before any code is written. EGM (Elephant-Goldfish Model) is a plugin for coding agents such as Claude Code, Codex and Antigravity that adds a structured workflow for designing features before implementation. A deep-context "elephant" agent, which holds the project's background and earlier decisions, explores the problem and drafts a specification. Then "goldfish" reviewers, which start with fresh context and see only the document and its referenced source material, look for unstated assumptions, unclear requirements and implementation risks.

Is elephant-goldfish-model free to use? What license does it have?

elephant-goldfish-model is open source under the Apache-2.0 license. Check the license terms before using it in commercial products.

Is elephant-goldfish-model still maintained?

Actively maintained. The last commit to elephant-goldfish-model was on Nov 7, 2026.

What can I use elephant-goldfish-model for?

Designing a feature that needs architectural decisions before any code is written. Stress-testing a spec for hidden assumptions before handing it to a coding agent. Writing documentation for an existing codebase and checking it for drift over time.

How do I install elephant-goldfish-model?

Add the plugin marketplace in Claude Code: claude plugin marketplace add google/elephant-goldfish-model Install the EGM plugin: claude plugin install egm@egm Start a new session, then run the brainstorm skill on a feature that needs design decisions: /egm:egm-brainstorm

Where can I get elephant-goldfish-model?

The source code and installation instructions are on GitHub: https://github.com/google/elephant-goldfish-model