# Double Check > MasterMind: Double-check - Skill: `mehrad-dm/double-check` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add mehrad-dm/double-check` - Raw SKILL.md: https://api.skillmd.com/api/skills/mehrad-dm/double-check/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: mehrad-dm (https://skillmd.com/u/mehrad-dm) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/mehrad-dm/double-check --- # MasterMind: Double-check You are about to hand over something you believe. Belief is not evidence (`~/.mastermind/engineering/core/rigor.md` → Report against evidence), and the check that catches a wrong claim has to happen while the work is still moving, not after the user has acted on it. Claim: **$ARGUMENTS**. The kernel's rule: **whatever did the work doesn't get to grade it**: is the entire mechanism here. This applies it to a *claim*, not only to a diff. ## The five moves 1. **Claim.** Write the belief you are about to act on or hand over, in **one sentence**: *"the retry loop now handles the expired-token case."* A paragraph means several claims, doubt them one at a time. The claim stays with you; it is the thing under test, not context to share. 2. **Extract.** Split it into the **artifact** (the code, the design, the answer, the diagnosis) and the **contract** it must satisfy (the requirement, the spec line, the invariant, the question actually asked). **If you can't write the contract down, stop and get one.** Without it there is no bar, and any reviewer defaults to grading your intent. 3. **Doubt.** Dispatch a reviewer in a fresh context with **the artifact and the contract, nothing else**. Brief it adversarially: > Find what is wrong with this. Assume the author is overconfident. Do not validate and do not > summarize: report what fails the contract, or state plainly that you could not find anything > after thorough examination. **Hand the artifact over via a file or stdin.** Never interpolate it into a shell-quoted argument: code and prompts carry backticks, `$(...)`, and quotes that truncate the message or execute in your shell. A clipped artifact reviews clean for the worst reason: the flaw didn't survive the paste. **Never pass it your claim.** The excuse is always *"it'll review faster with the context"*: but the context you're about to add is your conclusion, and a reviewer handed a conclusion hunts for reasons it holds. You would be buying agreement and calling it review. 4. **Reconcile.** Take each finding through these in order and stop at the first that fits: 1. **It misread the contract**: the contract was ambiguous, not the artifact wrong. Then **rewrite the contract and run the cycle again**; this class is where self-serving reconciliation hides, so it costs a cycle rather than discarding a finding. 2. **Valid and actionable**: fix it. 3. **Valid, and a trade-off worth accepting**: park it with the reason *and* the cost, in writing. 4. **Noise**: drop it, and name which ones you dropped. **Write each verdict in one line: ` → · `.** Nothing else belongs in that line: no gratitude, no "you're absolutely right", no praise for the reviewer. Agreement language is the tell that you settled a finding socially instead of evaluating it. A reviewer is a function, not a colleague whose goodwill you need. 5. **Stop.** Bounded at **three cycles**, then every open finding exits as fixed · parked-with-a-reason · **blocked** (handed to the human): the same close-out, in the same words, `build` step 6 runs (`~/.mastermind/skills/build/SKILL.md`), including its two prohibitions. ## The red flag: doubt theater Count it, don't feel it. **Across two or more cycles where the reviewer surfaced substantive findings, how many did you classify actionable?** Zero means you are validating, not doubting. Stop the loop there. Hand the reviewer's findings to the human **unreconciled**, alongside your reasoning for each, and let them adjudicate. A reviewer that keeps finding real things while you keep finding reasons they don't apply is not evidence of a clean artifact. It is evidence of a broken judge, and the judge is you. ## Doubt vs. `code-reviewer` `code-reviewer` (`~/.mastermind/agents/code-reviewer.md`) reviews a **diff that already exists**, at diff scope, and returns ranked must-fix/should-fix/nits for a human to decide on, it proposes and never applies. Doubt interrogates a **claim still in flight**, which is often not code at all: a diagnosis, a design call, an answer, a "this works" you're one sentence from saying. It ends with *your* written verdict on every finding, before the user sees anything. When the artifact is a finished diff, that is `code-reviewer`: and `build` step 6 already runs it. Don't wrap one in the other.