Google EGM: design first, code later, free under Apache 2.0

Google has published an open-source plugin called the Elephant-Goldfish Model, or EGM. According to the source, it makes your coding agent design a feature properly before it writes any code. An Elephant agent with full context writes the design document, and fresh, zero-context Goldfish subagents review it. The plugin installs into Claude Code, Codex and Antigravity.

The Goldfish reviewers only see the design document and the files it points to. According to the source, that narrow view lets them catch the shared assumptions you and your agent never wrote down. In Claude Code every command uses the /egm: prefix. Brainstorm sends out six Goldfish lenses in parallel, then draft, review and resolve take you to an approved design. The review skill bans flattery. If your harness can't create fresh subagents, EGM stops the review instead of faking it in the same context.

EGM ships extra skills beyond the core loop. One bootstraps README maps for an existing codebase. Another reports drift between your design docs and the code. On cost, the source states that five or six fresh reviewers burn a lot of tokens, so a $20 Claude or Codex plan will hit its limits quickly. The source also says the plugin is not meant for small bug fixes.

ClinePass is $9.99 a month with open models such as Kimi, GLM 5.3 and DeepSeek V4.1 Flash, according to the source. That lets you run several review rounds and use different models for the Elephant and the Goldfish. Cline supports SKILL.md skills and subagents, so EGM can run in Cline or as read-only Cline workers inside PandaCode. The source's verdict is that running EGM in Cline with ClinePass is a really good combo for $10 a month; that is the reviewer's opinion, not a measured result.

The source notes that Google built first-class install instructions for Claude Code, Codex, Claude Cowork and ChatGPT Work, not just for its own Antigravity agent. It reads this as Google building for the harnesses where developers already are. The plugin is free and licensed under Apache 2.0. The source's closing line is that the process matters more than the harness you run it in. The token burn and the review quality described here are the source's account, not something measured independently.