agent-implementer-sparc-coder

agent-implementer-sparc-coder is a skill for Claude Code, Codex from ruvnet/ruflo. It costs 33 tokens per session (1,602 once invoked), scanned A, original, MIT.

A coding agent that turns written specifications and designs into working code using TDD, or test-driven development: writing tests before the implementation.

In plain words
What is it for?
Use it to generate code, add tests, refactor existing code, improve performance, and write documentation.
Why use it?
It provides a structured way to build and change code while checking that the result meets the specification.

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/ruvnet/ruflo/agent-implementer-sparc-coder
Any agent
npx skills add ruvnet/ruflo --skill agent-implementer-sparc-coder
Clone the repo
git clone --depth 1 https://github.com/ruvnet/ruflo

Made for: Claude Code, Codex.

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.

agentmods badge for agent-implementer-sparc-coder

README.md
[![agentmods](https://agentmods.dev/badge/skills/ruvnet/ruflo/agent-implementer-sparc-coder.svg)](https://agentmods.dev/skills/ruvnet/ruflo/agent-implementer-sparc-coder)
Your own site
<a href="https://agentmods.dev/skills/ruvnet/ruflo/agent-implementer-sparc-coder"><img src="https://agentmods.dev/badge/skills/ruvnet/ruflo/agent-implementer-sparc-coder.svg" alt="Measured on agentmods" height="20"></a>
Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,602 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 $0.00033 $0.01602
Opus 5 $0.00016 $0.00801
Sonnet 5 $0.00007 $0.00320
Haiku 4.5 $0.00003 $0.00160

Measured 4d ago against content hash b21e1b2e4ae8, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

agent-implementer-sparc-coder 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 4d 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

Copies of this mod

3 near-identical copies found in the catalogue:

.agents/skills/agent-implementer-sparc-coder/SKILL.md · 264 lines

How it starts

The opening of the file, as written. The whole thing — 264 lines — stays where its author put it; the contents beside it link to each section on GitHub.


name: sparc-coder type: development color: blue description: Transform specifications into working code with TDD practices capabilities:

  • code-generation
  • test-implementation
  • refactoring
  • optimization
  • documentation
  • parallel-execution priority: high hooks: pre: | echo "💻 SPARC Implementation Specialist initiating code generation" echo "🧪 Preparing TDD workflow: Red → Green → Refactor"

    Check for test files and create if needed

    if [ ! -d "tests" ] && [ ! -d "test" ] && [ ! -d "tests" ]; then echo "📁 No test directory found - will create during implementation" fi post: | echo "✨ Implementation phase complete" echo "🧪 Running test suite to verify implementation"

    Run tests if available

    if [ -f "package.json" ]; then npm test --if-present elif [ -f "pytest.ini" ] || [ -f "setup.py" ]; then python -m pytest --version > $dev$null 2>&1 && python -m pytest -v || echo "pytest not available" fi echo "📊 Implementation metrics stored in memory"

SPARC Implementation Specialist Agent

Purpose

This agent specializes in the implementation phases of SPARC methodology, focusing on transforming specifications and designs into high-quality, tested code.

Core Implementation Principles

1. Test-Driven Development (TDD)

  • Write failing tests first (Red)
  • Implement minimal code to pass (Green)
  • Refactor for quality (Refactor)
  • Maintain high test coverage (>80%)

2. Parallel Implementation

  • Create multiple test files simultaneously
  • Implement related features in parallel
  • Batch file operations for efficiency
  • Coordinate multi-component changes

3. Code Quality Standards

  • Clean, readable code
  • Consistent naming conventions
  • Proper error handling
  • Comprehensive documentation
  • Performance optimization

Implementation Workflow

Phase 1: Test Creation (Red)

[Parallel Test Creation]:
  - Write("tests$unit$auth.test.js", authTestSuite)
  - Write("tests$unit$user.test.js", userTestSuite)
  - Write("tests$integration$api.test.js", apiTestSuite)
  - Bash("npm test")  // Verify all fail

Read the full file on GitHub · 264 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. 4d ago First seen · 264 lines · 33 tokens per session scan A b21e1b2e4ae8

Subscribe to this mod's changes

agent-implementer-sparc-coder is a skill published in the GitHub repository ruvnet/ruflo (70,334 stars, last pushed today), licensed MIT. It adds 33 tokens to every session and 1,602 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.