Applies language-agnostic and backend technical decision criteria, anti-pattern detection, debugging, and quality gates.
SkillScore82Maintained
Automatic
◆Coding pack
Last verified 8/18/2026
What it changes
Passed 18 of 22 test cases with the skill, and 15 of 22 without it.
Without skill68%
With skill82%
Checks it passed that the model alone missed
Logs the fallback activation once while redacting sensitive data
Explicitly records low certainty status before writing production code
Recommends performing a root-cause analysis like 5 Whys before applying a patch
and 1 more in the full report
4 fixed14 passed either way3 still failing1 broke
Pass-rate lift
+14 pp
Tokens
+120%
Agent turns
0%
Response time
-22%
Model gemini-3.6-flashMeasured 8/18/2026v218 of 22 cases passed with skill
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 4 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 4
Prompt
A developer wants to adopt a custom logging library import pattern found in a nearby legacy utility file in `src/utils/old_logger.ts`. What check must be performed before adopting this pattern in new feature code?
What was checked, without and with the skill
Checked
Without skill
With skill
Verifies that the pattern is representative across the repository rather than relying solely on nearby files
Missed
Passed
case-18 · gemini-3.6-flash · 8/18/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md252 linessingle file
AI Developer Guide - Technical Decision Criteria and Anti-pattern Collection
Value-First Engineering
Explore broadly, then converge on the lowest-lifecycle-cost solution that delivers the required user, operator, or maintainer value while keeping the system correct and maintainable.
Resolve verified problems within confirmed scope or dependencies required for the outcome; report other findings with evidence for a scope decision.
Introduce capabilities, infrastructure, abstractions, or speculative edge-case handling when a current outcome, verified constraint, or evidence-backed material risk requires them.
Treat behavior-preserving maintenance inside the confirmed responsibility as current maintainer value when repository evidence shows it reduces change ambiguity, duplicate ownership, defect risk, or future implementation and verification cost without expanding observable product scope.
Technical Anti-patterns (Red Flag Patterns)
Pause the affected decision and review the design when detecting the following patterns:
Code Quality Anti-patterns
Duplicating one responsibility across independently maintained locations - Review whether the duplicated logic has one change reason and should have one owner
Multiple responsibilities mixed in a single file - Violates Single Responsibility Principle (SRP)
Defining same content in multiple files - Violates DRY principle
Making changes without checking dependencies - Potential for unexpected impacts
Disabling code with comments - Should use version control
"Make it work for now" thinking - Accumulation of technical debt
Patchwork implementation - Unplanned additions to existing code
Optimistic implementation of uncertain technology - Designing unknown elements assuming "it'll probably work"
Symptomatic fixes - Surface-level fixes that don't solve root causes
Unplanned large-scale changes - Lack of incremental approach
Fail-Fast Fallback Design Principles
Core Principle
Make all errors visible and traceable with full context. Prioritize primary code reliability over fallback implementations. Excessive fallback mechanisms mask errors and make debugging difficult.
Implementation Guidelines
Default Approach
Give every failure an explicit outcome: propagate it, translate it to the boundary's error contract, or recover through an accepted fallback
Make failures explicit: Errors should be visible and traceable
Preserve error context: Include original error information when re-throwing