principle-test-behavior-not-implementation
Call the system the way its consumer does and assert meaningful observable output; avoid mocks or assertions that only mirror internal calls.
Skill by TheOnlyFusionCube
Install
Works with Claude Code, Claude apps, Codex, Cursor, Gemini CLI, GitHub Copilot, VS Code, OpenCode, Goose, Windsurf. Read the repository before you give any tool access to your data.
npx agentmarket install skill/theonlyfusioncube-principle-test-behavior-not-implementation
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About
Use cases: testing, writing
Reviews
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Permissions
What this skill can do and what it asks for, from its SKILL.md. Checked Oct 25, 2026.
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- None found
Network hosts it talks to 1
codeload.github.com· found in install command
Files it touches
~/.claude/skills/principle-test-behavior-not-implementation
What's inside
- Skill name
principle-test-behavior-not-implementation- Description
- Call the system the way its consumer does and assert meaningful observable output; avoid mocks or assertions that only mirror internal calls. Use when when writing or evaluating tests.
- License
- MIT
- Instructions
- 17 lines in SKILL.md · view on GitHub
Files (1)
- SKILL.md
SKILL.md (first lines)
# Test Behavior, Not Implementation ## Trigger When writing or evaluating tests. ## Rule Call the system the way its consumer does and assert meaningful observable output; avoid mocks or assertions that only mirror internal calls. ## Application 1. Name the concrete decision this principle changes. 2. Apply the rule to that decision, not as a decorative citation. 3. Prefer evidence from the current repository/runtime over generic preference. 4. If the principle conflicts with an explicit user constraint, keep the constraint and state the tradeoff.
From TheOnlyFusionCube/potetos-for-everyone, MIT.
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Signals
- Stars
- 16
- Forks
- 1
- Open issues
- 0
- Last commit (this folder)
- Sep 8, 2026 (1 month ago)
- Last release
- Sep 10, 2026 (1 month ago)
From GitHub (fetched Oct 24, 2026).
Details
- License
- MIT
- First seen
- Oct 24, 2026
- Last checked
- Oct 24, 2026
- Source
- GitHubgithub-graphql
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- 0.615score
benchmark-checklist
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Vet a perf measurement (limiter, tuning, limits, errors, repeatability, relevance, and whether the work happened) before you report or act on it.
SkillAFreshness: A★ 16Claude Code +9 - 0.615score
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SkillAFreshness: A★ 16Claude Code +9 - 0.600score
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Validate and normalize at boundaries, trust internal invariants, and keep business logic free of adapter noise.
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Remove dead weight and obsolete paths first; build on the simpler remaining system.
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Cite this page
principle-test-behavior-not-implementation skill. Agent Mart. https://agentmart.dev/skills/theonlyfusioncube-principle-test-behavior-not-implementation (last updated 2026-10-24)