mcp-devils-advocate

flowchart TD
    S[start_review claim + mode] --> M{mode}
    M -->|devils_advocate| C["counterarguments<br/>≥3, ≥2 categories, severity 1–5"]
    C --> D{any severity ≥ 3?}
    D -->|yes| R["rebuttals<br/>one per severe counterargument"]
    D -->|no| V
    R --> V[all phases complete]
    M -->|premortem| P1[setup: horizon] --> P2["failure_causes<br/>≥4, likelihood × impact"]
    P2 --> P3{any score ≥ 9?}
    P3 -->|yes| P4["mitigations<br/>action + residual risk"] --> V
    P3 -->|no| V
    M -->|assumptions| A1["assumptions<br/>≥4, load_bearing + evidence"]
    A1 --> A2{unverified load-bearing?}
    A2 -->|yes| A3["tests<br/>cheapest verification"] --> V
    A2 -->|no| V
    M -->|steelman| T1["strongest_case<br/>≥3 points for the opposing side"]
    T1 --> T2["responses<br/>concede or counter each"] --> V
    V --> G["get_verdict<br/>report + risk score + assessment"]

pip install -e .

{
  "mcpServers": {
    "devils-advocate": {
      "command": "python",
      "args": ["/absolute/path/to/server.py"]
    }
  }
}

claude mcp add devils-advocate -- python /absolute/path/to/server.py

{
  "review_id": "rev-k4d7",
  "status": "active",
  "instructions": {
    "phase": "counterarguments",
    "goal": "Attack the claim as a devil's advocate...",
    "item_format": {
      "text": "str, >= 30 characters — the counterargument, concrete and falsifiable",
      "category": "one of: evidence, incentives, base_rates, alternatives, second_order, scope",
      "severity": "int 1-5 — how damaging to the claim if true (5 = fatal)"
    },
    "rules": [
      "Submit at least 3 counterarguments (send them all in one call).",
      "Use at least 2 distinct categories.",
      "Every counterargument with severity >= 3 must be rebutted in the next phase — assign severity honestly."
    ]
  }
}

submit("rev-k4d7", [
  {"text": "Full rewrites of working systems fail or massively overrun far more often than they succeed; incremental strangler migrations have much better base rates.", "category": "base_rates", "severity": 4},
  {"text": "The team has zero production Rust experience; hiring and ramp-up costs will land exactly while feature delivery is frozen.", "category": "evidence", "severity": 4},
  {"text": "Profiling shows the bottleneck is the database layer, not CPU — a rewrite optimizes the part that isn't slow.", "category": "alternatives", "severity": 5},
  {"text": "Engineers pushing the rewrite are the ones who want Rust on their CV — incentives are not aligned with the business case.", "category": "incentives", "severity": 2}
])

submit("rev-k4d7", [
  {"index": 0, "verdict": "partially_holds", "justification": "True in general, but we can scope the rewrite to the two stateless services first, which is effectively a strangler migration."},
  {"index": 1, "verdict": "holds", "justification": "No honest rebuttal: nobody on the team has shipped Rust, and the hiring market for it is thin in our region."},
  {"index": 2, "verdict": "holds", "justification": "The profiling data is real — the p99 latency lives in Postgres queries. A Rust rewrite does not touch that."}
])

{
  "review_id": "rev-k4d7",
  "claim": "We should rewrite our backend in Rust",
  "mode": "devils_advocate",
  "risk_score": {"value": 2, "scale": "0-3 counterarguments that held after rebuttal"},
  "assessment": "claim refuted",
  "assessment_reason": "Of 3 rebutted counterargument(s): 2 hold, 1 partially hold, 0 refuted; a severity-5 counterargument holds. Rules: refuted if >=2 hold or any severity-5 holds; ..."
}

pip install -e ".[dev]"
python -m pytest