hydralisted

<!-- v2.0: per ADR docs/adr/0001-execution-substrate.md (Option C, accepted 2026-05-23), interactive /hydra runs in THIS harness (Agent tool + codex-companion), so SKILL.md is the living product surface. Prompt-level v2.0 wins land here directly (Echo advisor; chairman grounding + suspicious-verdict gate). The Python core in hydra/ is scoped to the bench (deterministic citation-grounding + reproducible scoring) -- it does NOT replace this runtime. Design context: docs/specs/2026-04-17-hydra-2.0-core-design-v2.md. --> # Hydra Four advisors analyze your code from different angles by default (standard mode) -- including Echo, which reviews AI-assisted-development failure modes -- then three peer reviewers cross-examine them and a chairman synthesizes the verdict. Escalate to deep mode for the full council: six advisors plus cross-model (Codex) diversity. Standard mode runs 4 advisors + 3 reviewers + chairman on Opus (~$0.70-1.20); add `--no-review` for the fast 4-advisor path (~$0.35-0.65). Deep mode adds 2 more advisors (including 2 Codex) and cross-model diversity, with the reviewers examining all 6 (~$1.50-2.50). Reference files in `references/` define all prompts and protocols -- read them at the relevant step. **Use this skill when** you need architecture decisions, security audits, tradeoff analysis, pre-merge deep reviews, or "what am I missing" answers -- anywhere multiple independent perspectives beat a single reviewer. **Do not use** for s