Google's open-source spec-driven development plugin: An "Elephant" agent with full context drafts design documents, while a "Goldfish" sub-agent without prior conversation history performs a cold review, helping you identify implicit assumptions and gaps before writing code.
Stars 3182 (+64 / 24h)
Reasoning
- The workflow consists of brainstorm (generate concept brief) → draft (draft design_draft.md section by section) → review (a newly spawned sub-agent reviews the design, clarity, code alignment, and implementation plan across five stages)
- Additional features include resolve (process review comments item by item), bootstrap (add documentation to existing codebases), review loop, and drift report (compare documentation with current code)
- Officially stated to be used by thousands of Google engineers; the author explicitly notes that small, clear bug fixes do not require this workflow
Usage
- Claude Code: Run
claude plugin marketplace add google/elephant-goldfish-model, thenclaude plugin install egm@egm. Use the command prefix/egm:, e.g.,/egm:egm-brainstorm - Codex: Run
codex plugin marketplace add google/elephant-goldfish-model, thencodex plugin add egm@egm. Select the corresponding skill in the skill selector - Antigravity:
agy plugin install https://github.com/google/elephant-goldfish-model；装好后开新会话
Risks
- Reviews depend on environments capable of spawning new sub-agents; if this is not possible, EGM will halt the review process
- The README states that this is not an officially supported Google product, and reviews cannot replace testing and human judgment; License: Apache 2.0