feature-implementation

A software-development workflow for implementing features with separate checks intended to catch mistakes in AI-generated code. It uses written requirements, implementation, testing from the specification, and attempts to break the result.

In plain words
What is it for?
It is for defining an API contract, implementing a feature, testing against the specification, trying to break the implementation, and checking whether the tests can detect failures.
Why use it?
AI-written code and AI-written tests can share the same assumptions and miss the same bug. Independent verification adds checks from fresh perspectives.

Command for Claude Code

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 commands/keychain-io/trustable-ai/feature-implementation
Clone the repo
git clone --depth 1 https://github.com/keychain-io/trustable-ai

Made for: Claude Code.

Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 3,587 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 $0.00000 $0.03587
Opus 5 $0.00000 $0.01793
Sonnet 5 $0.00000 $0.00717
Haiku 4.5 $0.00000 $0.00359

Measured 2d ago against content hash e8ccb9b67380, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

feature-implementation 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.

.claude/commands/feature-implementation.md · 546 lines

How it starts

The opening of the file, as written. The whole thing — 546 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Feature Implementation Workflow (Adversarial Verification)

Project: trusted-ai-development-workbench Workflow: Feature Implementation with Adversarial Verification Purpose: Implement features with procedural safeguards against AI-generated bugs

Output Formatting Requirements

IMPORTANT: Use actual Unicode emojis in reports, NOT GitHub-style shortcodes.


The Problem This Workflow Solves

AI-generated code often contains subtle bugs. AI-generated tests often miss those same bugs because they share the same blind spots. This workflow uses adversarial multi-agent verification with fresh context windows for each specialized agent.

┌─────────────────────────────────────────────────────────────────────────┐
│  This Workflow (Adversarial Verification with Agent Slash Commands)     │
│                                                                         │
│  1. /senior-engineer → Creates API contract                            │
│  2. /senior-engineer → Implements feature                              │
│  3. /tester → Tests from SPEC ONLY (no code!)             │
│  4. /tester → Tries to break code                         │
│  5. /tester → Verifies tests can fail                  │
│  6. /tester → Resolves code/test/spec conflicts              │
│                                                                         │
│  Each agent command spawns a FRESH CONTEXT WINDOW via Task tool        │
└─────────────────────────────────────────────────────────────────────────┘

Prerequisites

  • Work item ID with clear acceptance criteria
  • Specification file at docs/specifications/ (from sprint-planning)
  • Project codebase with existing test infrastructure

Initialize Workflow

First, collect the work item information:

# Initialize work tracking adapter
import sys
sys.path.insert(0, ".claude/skills")
from work_tracking import get_adapter

adapter = get_adapter()
print(f"📋 Work Tracking: {adapter.platform}")

work_item_id = input("Enter work item ID (e.g., 1001): ")
sprint_number = input("Enter sprint number: ")

# Load work item from adapter
try:
    work_item = adapter.get_work_item(int(work_item_id))
    print(f"✅ Loaded work item #{work_item_id}: {work_item.get('title', 'Untitled')}")

    # Extract fields
    work_item_title = work_item.get('title', '')
    work_item_description = work_item.get('description', '')
    acceptance_criteria = work_item.get('acceptance_criteria', [])
except Exception as e:
    print(f"❌ Failed to load work item #{work_item_id}: {e}")
    print("   Make sure the work item exists in azure-devops")
    exit(1)

# Load specification file (if it exists, otherwise use work item description)
from pathlib import Path
spec_file = Path(f"docs/specifications/sprint-{sprint_number}/{work_item_id}-spec.md")
if spec_file.exists():
    specification = spec_file.read_text()
    print(f"✅ Loaded specification from {spec_file}")
else:
    print(f"⚠️ Specification file not found: {spec_file}")
    print("   Using work item description as specification")
    specification = work_item_description

Read the full file on GitHub · 546 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 · 546 lines · 0 tokens per session scan A e8ccb9b67380

Subscribe to this mod's changes

feature-implementation is a command published in the GitHub repository keychain-io/trustable-ai (2 stars, last pushed 6mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 3,587 tokens. 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 2026-08-31.