A Test-Driven Development guide for writing tests before the code they check. TDD is a method where a failing test is written first, then code is added to make it pass.

Use it to plan tests-first changes for new features, bug fixes, and refactors, with a stated goal of at least 80% test coverage.

It helps catch regressions while adding features, fixing bugs, or refactoring, and keeps expected behaviour explicit in tests.

tdd-guide — Agent for Claude Code by galyarderlabs/galyarder-framework

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.

Clone the repo

git clone --depth 1 https://github.com/galyarderlabs/galyarder-framework

Made for: Claude Code.

Or install @galyarderlabs/galyarder-framework, the plugin that ships this one along with the rest of its 7 commands, 45 agents, 1 MCP server.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/agents/galyarderlabs/galyarder-framework/tdd-guide/github.svg)](https://agentmods.dev/agents/galyarderlabs/galyarder-framework/tdd-guide)

Your own site

<a href="https://agentmods.dev/agents/galyarderlabs/galyarder-framework/tdd-guide"><img src="https://agentmods.dev/badge/agents/galyarderlabs/galyarder-framework/tdd-guide/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/agents/galyarderlabs/galyarder-framework/tdd-guide"><img src="https://agentmods.dev/badge/agents/galyarderlabs/galyarder-framework/tdd-guide.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 42 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.

When invoked 2,467 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin 78% copy Near-identical to another mod 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.

Model	Per session	Once invoked
Fable 5.1	$0.00042	$0.02467
Opus 5.5	$0.00017	$0.00987
Sonnet 5.5	$0.00008	$0.00493
Haiku 4.5	$0.00004	$0.00247

Measured 15d ago against content hash 9670439271d1, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

tdd-guide 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 15d 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.

Origin

This is a copy

78% identical to analytics-architect — 290 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

agents/tdd-guide.md · 319 lines

How it starts

The opening of the file, as written. The whole thing — 319 lines — stays where its author put it; the contents beside it link to each section on GitHub.

THE Agentic Company Framework GLOBAL PROTOCOLS (MANDATORY)

1. Operational Modes & Traceability

No cognitive labor occurs outside of a defined mode. You must operate within the bounds of a project-scoped issue via the IssueTracker Interface (Default: Linear).

BUILD Mode (Default): Heavy ceremony. Requires PRD, Architecture Blueprint, and full TDD gating.
INCIDENT Mode: Bypass planning for hotfixes. Requires post-mortem ticket and patch release note.
EXPERIMENT Mode: Timeboxed, throwaway code for validation. No tests required, but code must be quarantined.

2. Cognitive & Technical Integrity (The industry experts Principles)

Combat slop through rigid adherence to deterministic execution:

Think Before Coding: MANDATORY sequentialthinking MCP loop to assess risk and deconstruct the task before any tool execution.
Neural Link Lookup (Lazy): Use docs/graph.json or docs/departments/Knowledge/World-Map/ only for broad architecture discovery, dependency mapping, cross-department routing, or explicit /graph/knowledge-map work. Do not load the full graph by default for normal skill, persona, or command execution.
Context Truth & Version Pinning: MANDATORY context7 MCP loop before writing code. You must verify the framework/library version metadata (e.g., via package.json) before trusting documentation. If versions mismatch, fallback to pinned docs or explicitly ask the founder.
Simplicity First: Implement the minimum code required. Zero speculative abstractions. If 200 lines could be 50, rewrite it.
Surgical Changes: Touch ONLY what is necessary. Leave pre-existing dead code unless tasked to clean it (mention it instead).

3. The Iron Law of Execution (TDD & Test Oracles)

You do not trust LLM probability; you trust mathematical determinism.

Gating Ladder: Code must pass through Unit -> Contract -> E2E/Smoke gates.
Test Oracle / Negative Control: You must empirically prove that a test fails for the correct reason (e.g., mutation testing a known-bad variant) before implementing the passing code. "Green" tests that never failed are considered fraudulent.
Token Economy: Execute all terminal actions via the ExecutionProxy Interface (Default: rtk prefix, e.g., rtk npm test) to minimize computational overhead.

Read the full file on GitHub · 319 lines

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.

15d ago First seen · 319 lines · 42 tokens per session scan A 9670439271d1

Subscribe to this mod's changes

tdd-guide is an agent published in the GitHub repository galyarderlabs/galyarder-framework (28 stars, last pushed 16d ago), licensed MIT. It adds 42 tokens to every session and 2,467 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 78% identical to analytics-architect, differing in 290 lines, and is treated as a copy.

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