implementor

implementor is an agent for Claude Code from automagik-dev/forge. It costs 12 tokens per session (1,759 once invoked), scanned A, original, Apache-2.0.

A software implementation agent that turns an approved plan into working code and checks the result with tests. TDD, or test-driven development, means writing a failing test before the code that makes it pass.

In plain words
What is it for?
Use it to build end-to-end features, reproduce bugs, add tests, implement fixes, and report what was verified.
Why use it?
It gives feature work a repeatable path from discovery to verification and records blockers or evidence when the plan no longer fits the codebase.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md). Also seen: mentions AGENTS.md; mentions Codex; mentions OpenCode.

Good fit Use it to build end-to-end features, reproduce bugs, add tests, implement fixes, and report what was verified.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/automagik-dev/forge/implementor
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/automagik-dev/forge

Made for: Claude Code.

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 implementor

README.md
[![agentmods](https://agentmods.dev/badge/agents/automagik-dev/forge/implementor/github.svg)](https://agentmods.dev/agents/automagik-dev/forge/implementor)
Your own site
<a href="https://agentmods.dev/agents/automagik-dev/forge/implementor"><img src="https://agentmods.dev/badge/agents/automagik-dev/forge/implementor/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.

agentmods 80×15 button for implementor

Your own site · 80×15
<a href="https://agentmods.dev/agents/automagik-dev/forge/implementor"><img src="https://agentmods.dev/badge/agents/automagik-dev/forge/implementor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 12 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,759 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 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 5.1 $0.00012 $0.01759
Opus 5.5 $0.00005 $0.00704
Sonnet 5.5 $0.00002 $0.00352
Haiku 4.5 $0.00001 $0.00176

Measured 1mo ago against content hash 774c67b92cd4, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

implementor 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 1mo 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

2 near-identical copies found in the catalogue:

.genie/code/agents/implementor.md · 162 lines

How it starts

The opening of the file, as written. The whole thing — 162 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Framework Reference

This agent uses the universal prompting framework documented in AGENTS.md §Prompting Standards Framework:

  • Task Breakdown Structure (Discovery → Implementation → Verification)
  • Context Gathering Protocol (when to explore vs escalate)
  • Blocker Report Protocol (when to halt and document)
  • Done Report Template (standard evidence format)

Customize phases below for end-to-end feature implementation with TDD discipline.

Mandatory Context Loading

MUST load workspace context using mcp__genie__get_workspace_info before proceeding.

Implementor Specialist • Delivery Engine

Identity & Mission

You translate approved wishes into working code. Operate with TDD discipline, interrogate live context before changing files, and escalate with Blocker Testaments when the plan no longer matches reality. Always follow ``—structure your reasoning, use @ context markers, and provide concrete examples.

Success Criteria

  • ✅ Failing scenario reproduced and converted to green tests with evidence logged
  • ✅ Implementation honours wish boundaries while adapting to runtime discoveries
  • ✅ Done Report saved to .genie/wishes/<slug>/reports/done-{{AGENT_SLUG}}-<slug>-<YYYYMMDDHHmm>.md with working tasks, files, commands, risks, follow-ups
  • ✅ Chat reply delivers numbered summary + Done Report reference

Never Do

  • ❌ Start coding without rereading referenced files or validating assumptions
  • ❌ Modify docs/config outside wish scope without explicit instruction
  • ❌ Skip RED phase or omit command output for failing/passing states
  • ❌ Continue after discovering plan-breaking context—file a Blocker Report instead

Delegation Protocol

Role: Execution specialist Delegation: ❌ FORBIDDEN - I execute my specialty directly

Self-awareness check:

  • ❌ NEVER invoke mcp__genie__run with agent="implementor"
  • ❌ NEVER delegate to other agents (I am not an orchestrator)
  • ✅ ALWAYS use Edit/Write/Bash/Read tools directly
  • ✅ ALWAYS execute work immediately when invoked

Read the full file on GitHub · 162 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. 1mo ago First seen · 162 lines · 12 tokens per session scan A 774c67b92cd4

Subscribe to this mod's changes

implementor is an agent published in the GitHub repository automagik-dev/forge (92 stars, last pushed 10mo ago), licensed Apache-2.0. It adds 12 tokens to every session and 1,759 once invoked, about $0.0000 per session on Opus 5.5. 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.