Night Market Skill — ported from claude-night-market/leyline. For the full experience with agents, hooks, and commands, install the Claude Code plugin.

The default answer to "should we add this?" is no. The burden of proof is on the addition.

Additive Bias Defense#

Note (#444): Frontmatter declares provides.guidance, not provides.contract. The scrutiny questions are consumed by partner skills ( pensive:code-refinement, conserve:unbloat, imbue:scope-guard) that voluntarily embed them; no validator or hook in leyline enforces them directly. If a future contributor adds enforcement, restore the contract label and link the validator path here.

The Problem#

LLMs are additive by nature. They reinvent wheels, add unnecessary complexity, hallucinate issues and modify tests to justify them, and deviate from priorities. This contract provides a systemic defense.

The Scrutiny Questions#

Applied to every proposed addition -- code, files, abstractions, error handling, configuration:

1. Priority alignment: Is this a deviation from the current priority?
2. Criticality: Is it critical to implement at this juncture?
3. Simplicity: Does a simpler or more elegant solution exist?
4. Evidence: What evidence proves this is needed (not assumed)?
5. Consequence: What breaks if we do not add this?

If the proposer cannot answer questions 4 and 5 with concrete evidence, the addition is unjustified.

Anti-Pattern Detection#

PatternSignalChallengeWheel reinventionNew utility/helper overlapping existing code"Does X already do this?"Hallucinated issuesFix for a bug with no reproduction evidence"Show the failing test before the fix"Test manipulationTest changed to match behavior rather than spec"Did the spec change, or did you change the test?"Complexity creepAbstraction introduced for single use case"Is this the 3rd use, or the 1st?"Priority deviationWork not traceable to current task/spec"Which requirement does this serve?"Gold platingError handling or flexibility beyond need"What breaks without this?"

Burden of Proof Verdict#

After applying scrutiny questions and anti-pattern detection, produce a verdict:

VerdictMeaningActionjustifiedEvidence supports the additionProceedneeds_evidencePlausible but unprovenProvide evidence or removeunjustifiedNo evidence, likely biasRemove or justify

Integration Contract#

Review-oriented skills MUST consult this contract by:

1. Applying the 5 scrutiny questions to each addition
2. Scanning for the 6 anti-patterns
3. Producing a burden-of-proof verdict
4. Including the verdict in their output

Consuming Skills#

SkillIntegration Pointattune:war-roomProsecution Counsel role uses scrutiny questionssanctum:pr-reviewEvery added file/function challengedpensive:code-refinementRefactors pass "3rd use" testconserve:unbloatFindings feed removal candidatesattune:mission-orchestratorPlan sections scanned before user reviewimbue:justifyScrutiny questions extend audit protocol

Related Skills#

• imbue:karpathy-principles - "Simplicity First" and "Surgical Changes" principles invoke this contract from a higher-level four-principle synthesis
• See docs/quality-gates.md#skill-level-quality-gate-composition for the full gate-skill federation graph

The Subtraction Principle#

Rely less on AI and initial lines of thinking. Challenge yourself to think of a more elegant implementation or a simpler solution.

Before accepting any addition, ask: "Could I achieve this by removing code instead of adding it?" If yes, prefer the subtractive approach.