Yes. EGM fits because it can review an existing design document against the source code without requiring you to create a new specification first.

• The “Try a 60-second review on existing code” section explicitly supports /egm:egm-review docs/designs/webhooks.md; the review checks clarity, fit with the code, and the implementation plan.
• Goldfish uses a fresh subagent context and receives the document plus referenced source material, helping expose unstated assumptions.
• The review does not replace tests or human judgment; you still choose which findings to address and approve the design before implementation.
• The README documents Claude Code installation, but requires starting a new session after installation.

Yes. EGM fits because its skills can be invoked independently while still supporting a complete path from idea exploration to an approved specification.

• The “Choose a skill” section says Brainstorm, Draft, Resolve, Review, and other skills can be used when needed; the full sequence is optional.
• Brainstorm saves concepts_brief.md, Draft turns the brief or existing notes into design_draft.md, and Review evaluates that document independently.
• In Codex CLI, you select the corresponding EGM skill from the skill picker rather than copying Claude Code’s /egm: syntax, avoiding host-command mismatches.
• You retain responsibility for architectural trade-offs and approval; the project does not treat generated output as automatically ready for implementation.

Yes. EGM fits because it provides a dedicated drift report that compares registered documents with the current source code while leaving the correction decision to the team.

• The “Check for drift” example directly uses /egm:egm-drift-report docs/designs/; the agent compares each document in that folder with the current source.
• The getting-started workflow recommends saving approved specifications under docs/designs/, matching this maintenance model.
• Drift reporting identifies divergences but does not decide whether the document or code should change, so it is not automatic synchronization.
• The project is still v0.1.1 with two releases; the README does not demonstrate long-term stability for large, multi-repository, or complex-permission environments.

It depends. Antigravity CLI 1.4.8 can be used if the team consistently supplies the /egm: prefix and the session supports fresh subagents; otherwise independent review cannot work.

• The README says agy CLI commands should use the /egm: prefix. Version 1.4.8 does not auto-complete it like 1.4.10, so unprefixed commands cannot be relied on.
• Brainstorming and review require a session that can create fresh subagents; EGM stops the review when that capability is unavailable.
• The installation command is agy plugin install ..., and a new session is required after installation.
• The README does not promise a complete capability matrix for Antigravity 1.4.8, so usability depends on the host’s actual subagent support.

It depends. EGM supports configurable review loops, but its default draft and design-review workflows target software specifications; non-software documents require you to configure reviewers and standards yourself.

• The README explicitly says the built-in workflow targets software specifications, while other documents should use /egm-review-loop to choose reviewers and standards.
• “Choose a skill” lists Review loop for running a configured group of reviewers for a specific review task.
• This broadens the review workflow, but the project does not provide a built-in catalog of product, operations, or governance standards.
• Bootstrap and drift reporting apply to software codebases, so their code-comparison behavior should not be assumed for non-software documents.

It depends. EGM’s reviews require access to project context, design documents, and referenced source material, but the README does not promise data retention, model access, or sensitive-information handling for ChatGPT Work or Claude Code.

• Elephant uses project context, requirements, and prior decisions to draft specifications, while Goldfish reviews the document and referenced source material; therefore source-access scope is a prerequisite.
• The README provides setup guidance for ChatGPT Work and Claude Code but does not state whether enterprise data leaves the local environment, how redaction works, or whether permission isolation is supported.
• Apache 2.0 reduces licensing friction for internal customization, but the license does not replace data-governance controls for model services.
• Adoption for a restricted codebase depends on organizational approval of the host, model, agent permissions, and information flow—not on plugin functionality alone.