Skeptical Triage

Filter false positives from multi-angle review, security audit, QA regression flags, or any high-stakes judgment before it turns into a blocker.

Three rounds of skeptical self-review + an impartial arbiter, with a confidence score from the vote.

When to invoke

The 4-step pattern

Run these sequentially. Each round sees prior reasoning. Arbiter sees all rounds.

Round 1 — Reachability / Premise

Question: is the premise true?

• For security/reliability: can an external attacker reach this code path with untrusted input? Trace input flow backward from the bug site to its origin. If only trusted internal callers → lean INVALID.
• For regressions: does the failing behavior reproduce from a clean state on the target branch?
• For ADR trade-offs: is the constraint that forces the choice actually binding? (e.g. "we need <10ms p99" — is that real or aspirational?)

Output: {round: 1, verdict: VALID|INVALID|UNCERTAIN, reasoning: "...", crux: "single key fact"}

Round 2 — Verify cited defenses / counter-evidence

Question: are claimed defenses real and sufficient?

• Every cited defense → use Grep to find its actual implementation line.
• Resolve constant names to numeric values. MAX_BUF_SIZE is not a verified bound — #define MAX_BUF_SIZE 64 is.
• For regressions: is the cited "test covers this" actually asserting the right invariant?
• For ADR: is the cited benchmark/precedent real (grep for it, read it), or rumored?

If you cannot point to the line that enforces the defense, it does not exist.

Output: same JSON shape, with grep_used: true/false.

Round 3 — Missed angles

Question: what did Rounds 1-2 not consider?

• Error paths, integer overflow, race windows, different callers, platform differences
• Do NOT rehash prior rounds — add new evidence or concede
• For QA: retry logic masking the failure? Test pollution from another test?
• For ADR: option C that neither reviewer raised?

Output: same JSON shape.

Arbiter

Input: all 3 rounds + original finding/question + source code.

Question: final call — which side has the stronger evidence?

• Deliver single verdict: VALID|INVALID (no UNCERTAIN — make the call).
• Deliver one-sentence crux — the key fact the verdict turns on.
• If 3 prior rounds all said the same thing, only override with overwhelming new evidence and explain why.

Output:

{
  "verdict": "VALID",
  "crux": "memcpy at auth.c:142 copies network-controlled len bytes into 64-byte stack buffer with no bound check",
  "reasoning": "Rounds 1 and 3 verified attacker reach; Round 2 found no size check in 50 LOC radius; arbiter confirms no caller clamps len."
}

Hard rules

Burn these into every round's prompt:

1. Absence of defense → VALID, not UNCERTAIN. If you searched for a defense and did not find one, that is the answer. "Other code probably handles this" is not a valid defense.
2. A constant name is not a verified bound — only its resolved value is. Grep for the #define / const declaration.
3. Name the line or it does not exist. Vague references to "assumptions in this codebase" do not count.
4. Do not contradict your own conclusion in the same response. If you verified a defense is insufficient, that is the verdict. Stop searching for reasons to flip.
5. Code quality issue ≠ security vulnerability. Data race on diagnostic state, NULL check on internal-only API, UB only in debug builds → INVALID.
6. Trust your own reasoning. If you see the crux on first read, don't manufacture a counter-argument.

Confidence scoring

confidence = valid_rounds_before_arbiter / 3

• 100% (VVV) — 3/3 rounds VALID. Arbiter rubber-stamps unless it finds something brand-new.
• 67% (VVI or VIV or IVV) — majority VALID. Arbiter breaks tie with new evidence.
• 33% (IIV or IVI or VII) — majority INVALID. Arbiter usually confirms INVALID.
• 0% (III) — 3/3 INVALID. Arbiter rarely overrides.

Arbiter overrides the final verdict; confidence reflects the round vote for transparency. Record both in the output so humans can see where the arbiter diverged.

Applying triage results to severity

Once the arbiter returns:

Output schema

Every caller logs triage results to .great_cto/triage-log.jsonl (append-only, one JSON per line):

{
  "timestamp": "2026-04-19T12:34:56Z",
  "caller": "review|security-officer|qa-engineer|architect",
  "finding_id": "SEC-042",
  "file": "src/auth.c:142",
  "original_severity": "P0",
  "rounds": [
    {"round": 1, "verdict": "VALID",   "crux": "..."},
    {"round": 2, "verdict": "VALID",   "crux": "...", "grep_used": true},
    {"round": 3, "verdict": "INVALID", "crux": "..."}
  ],
  "arbiter": {"verdict": "VALID", "crux": "..."},
  "confidence": 0.67,
  "final_severity": "P0"
}

This log is how we measure whether triage earns its keep. Review it weekly:

# False-positive rate: how many findings the arbiter flipped to INVALID
jq 'select(.arbiter.verdict=="INVALID")' .great_cto/triage-log.jsonl | wc -l

# Average rounds-to-consensus (did we need all 3 or did R1+R2 agree?)
jq '[.rounds[].verdict] | unique | length' .great_cto/triage-log.jsonl

If FP rate < 10% after 50 triages — triage is filtering noise that wasn't there. Lower threshold or skip triage for that angle. If FP rate > 40% — original review prompt is too trigger-happy; tighten the angle rules.

Token budget

Per triaged finding: ~4 LLM turns (3 rounds + arbiter). At typical review sizes (~5-10 triaged findings per PR), total budget: 20-40 extra turns per /review. Batch when possible — one arbiter can handle multiple findings in a single call if their cruxes are independent.

For cost-sensitive runs (approval-level: auto on a huge PR), consider: triage only P0, leave P1 untriaged. Re-tune based on .great_cto/triage-log.jsonl data.

Anti-patterns

• Don't triage P2/advisory findings. The whole point is gate decisions. P2 is advisory — let the author see it and move on.
• Don't let rounds rehash each other. Round 3 prompt must say "add NEW evidence or concede." If 3 rounds produce identical reasoning, you wasted 2 turns.
• Don't skip the arbiter on UNCERTAIN. If all 3 rounds say UNCERTAIN, the arbiter's job is to decide — not to join the fog.
• Don't hide arbiter overrides. When the arbiter flips the majority vote, record both confidence (the vote) and final_verdict (the arbiter). Humans deserve to see the disagreement.