Claude Code plugin: Gemini as second-opinion assistant (validator, challenger, researcher, summarizer subagents + auto-trigger hooks)
Agent
Use proactively before destructive operations, when evaluating architectural choices, or when the main agent appears stuck in a pattern. Devil's advocate that argues at least 2 alternative approaches and 1 reason the current path is wrong. Returns structured JSON {alternatives, objections, mustaddress}.
Agent
Use proactively when a question involves post-training-cutoff information, live API docs, recent CVEs, library releases, or any claim that needs a primary source. Performs search-grounded research and deep research via Gemini. Never opines without a citation. Returns answer + citations.
Agent
Use proactively when finalizing a diff or PR for a generalist third-reviewer pass that the other agents do not cover: security, threading correctness, library/version drift, doc accuracy, dead code, and complexity. NOT for research (use gemini-researcher), claim validation (use gemini-validator), or devil's-advocate…
Agent
Use proactively at session start (BUILDRISKMAP) and before context compaction (SUMMARIZESESSIONSTATE). Compresses session history into structured summaries preserving decisions, discarded alternatives, and unresolved debt. Writes risk maps for new repositories.
Agent
Use proactively after a plan is finalized, after Claude claims a task is done, or before a destructive change. Validates the artifact against the original ask and flags gaps, hallucinations, and missed acceptance criteria. Returns structured JSON {verdict, gaps, hallucinations, nextactions}.