tdd

A Test-Driven Development workflow, where tests describing expected behavior are written before or alongside code. TDD means using tests to guide changes and prevent regressions.

In plain words
What is it for?
Use it to plan requirements, write unit, integration, or end-to-end tests, implement only what those tests require, and verify observable behavior.
Why use it?
It reduces the risk of adding a feature or fixing a bug without checking that the behavior works and stays working.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/smartfrog/opencode-froggy/tdd
Any agent
npx skills add smartfrog/opencode-froggy --skill tdd
Clone the repo
git clone --depth 1 https://github.com/smartfrog/opencode-froggy

Made for: Claude Code, Codex.

Per session 17 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 366 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00017 $0.00366
Opus 5 $0.00009 $0.00183
Sonnet 5 $0.00003 $0.00073
Haiku 4.5 $0.00002 $0.00037

Measured 2d ago against content hash 773800a6e3ee, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

tdd scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skill/tdd/SKILL.md · 45 lines

What it actually says

TDD Protocol

Core Principle

  • TDD First: Test-Driven Development is the default approach.
  • Goal: Prioritize behavioral correctness and regression safety over formal compliance.

Workflow

  1. Requirement Synthesis: Briefly summarize the requirements before coding.
  2. Test Specification: Write tests describing the expected behavior (unit, integration, or E2E).
  3. Implementation: Update the logic only to the extent required to satisfy those tests.

Mandatory Rules

  • No Test, No Code: Every new feature or bugfix must include relevant test coverage.
  • Black-Box Testing: Validate observable behavior, not internal implementation details.
  • Merge Requirement: Tests are mandatory for completion unless an explicit exception is documented.

Preferred Practice

  • Red-Green-Refactor: Start with a failing test whenever practical.
  • Right-Sized Testing:
    • Unit Tests: For pure logic and isolated functions.
    • Integration Tests: For system interactions and API boundaries.
    • E2E Tests: For critical user journeys and "happy paths."

Explicit Exceptions (Must be justified)

  • Pure refactoring (where behavior remains identical).
  • Exploratory spikes or R&D.
  • UI/Styling iterations where unit tests offer diminishing returns.
  • Complex integrations where mocking is counterproductive.
  • Emergency hotfixes (requires a follow-up ticket for test debt).

Quality Bar

  • Readability: Tests must serve as documentation for the feature.
  • Reliability: Tests must be deterministic (no flakes) and decoupled from implementation internals.
Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 45 lines · 17 tokens per session scan A 773800a6e3ee

Subscribe to this mod's changes

tdd is a skill published in the GitHub repository smartfrog/opencode-froggy (105 stars, last pushed 3mo ago), licensed MIT. It adds 17 tokens to every session and 366 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

Other skills, from other repositories

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

brainstorming

You MUST use this before any creative work - creating features, building components, adding functionality, or modifying behavior. Explores user intent, requirements and design before implementation.

obra/superpowers · 37 tokens

chat-pet-sprite-creation

Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.

microsoft/vscode · 53 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 tokens

agent-host-chat-contributions

Build and review cross-cutting agent-host chat behavior through lifecycle contributions. Use when adding turn lifecycle side effects, prompt or context injection, restored-history transformation, protocol-action observation, or when reviewing changes that add code to AgentSideEffects or AgentService.

microsoft/vscode · 56 tokens

auto-perf-optimize

Run agent-driven VS Code performance or memory investigations. Use when asked to launch Code OSS, automate a VS Code scenario, run the Chat memory smoke runner, capture renderer heap snapshots, take workflow screenshots, compare run summaries, or drive a repeatable scenario before heap-snapshot analysis.

microsoft/vscode · 62 tokens