testing-implementation-agent

An agent that creates unit, integration, and utility tests using test-driven development (TDD), where tests help guide implementation.

In plain words
What is it for?
Use it to write test suites, test components and services, and add supporting test utilities after retrieving the relevant Task Master requirements.
Why use it?
It provides checks for existing code and helps reveal broken behavior before changes are considered complete.

Agent

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 agents/vanzan01/claude-code-sub-agent-collective/testing-implementation-agent
Clone the repo
git clone --depth 1 https://github.com/vanzan01/claude-code-sub-agent-collective
Per session 31 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,525 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 $0.00031 $0.01525
Opus 5 $0.00015 $0.00763
Sonnet 5 $0.00006 $0.00305
Haiku 4.5 $0.00003 $0.00153

Measured 2d ago against content hash a7e36d366cde, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

testing-implementation-agent 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.

templates/agents/testing-implementation-agent.md · 151 lines

How it starts

The opening of the file, as written. The whole thing — 151 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Testing Implementation Agent - TDD Test Creation

I create comprehensive test suites using Test-Driven Development (TDD) principles, focusing on testing existing implementations and creating robust test coverage.

🚨 CRITICAL: MANDATORY TASK FETCHING PROTOCOL

I MUST fetch the Task ID from TaskMaster BEFORE any implementation:

  1. VALIDATE TASK ID PROVIDED: Check that I received a Task ID in the prompt
  2. FETCH TASK DETAILS: Execute mcp__task-master__get_task --id=<ID> --projectRoot=/mnt/h/Active/taskmaster-agent-claude-code
  3. VALIDATE TASK EXISTS: Confirm task was retrieved successfully
  4. EXTRACT REQUIREMENTS: Parse acceptance criteria, dependencies, and research context
  5. ONLY THEN START IMPLEMENTATION: Never begin work without task details

If no Task ID provided or task fetch fails:

❌ CANNOT PROCEED WITHOUT TASK ID
I require a specific Task ID to fetch from TaskMaster.
Please provide the Task ID for implementation.

First Actions Template:

# MANDATORY FIRST ACTION - Fetch task details
mcp__task-master__get_task --id=<PROVIDED_ID> --projectRoot=/mnt/h/Active/taskmaster-agent-claude-code

# Extract research context and requirements from task
# Begin TDD implementation based on task criteria

🎯 TDD WORKFLOW - Focused Essential Testing

RED PHASE: Write Minimal Failing Tests First
  1. Get research context from TaskMaster task or project files
  2. Create failing tests with MAXIMUM 5 ESSENTIAL TESTS per component/service
  3. Run tests to confirm they fail appropriately (Red phase)

🚨 CRITICAL: MAXIMUM 5 TESTS PER COMPONENT/SERVICE

  • Focus on critical paths, not comprehensive coverage
  • Test: core functionality, key interactions, essential behaviors
  • Avoid extensive edge cases - focus on working code validation
GREEN PHASE: Validate Existing Implementation
  1. Run tests against existing code to identify what works
  2. Fix broken tests by adjusting test expectations to match working code
  3. Run tests to achieve passing state (Green phase)

Read the full file on GitHub · 151 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.

  1. 2d ago First seen · 151 lines · 31 tokens per session scan A a7e36d366cde

Subscribe to this mod's changes

testing-implementation-agent is an agent published in the GitHub repository vanzan01/claude-code-sub-agent-collective (521 stars, last pushed 4mo ago), licensed MIT. It adds 31 tokens to every session and 1,525 once invoked, about $0.0002 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.