Junior Plan Implementer

Junior Plan Implementer is an agent for Claude Code from semihkayan/codeweave-mcp. It costs 26 tokens per session (767 once invoked), scanned A, original, Apache-2.0.

A coding-agent role that carries out a written implementation plan exactly as specified. It reads the relevant code, resolves limited ambiguities using existing conventions, and checks the work as it goes.

In plain words
What is it for?
Use it to implement well-defined coding plans, reuse existing project patterns, run fast quality checks, and report when the plan is too unclear to implement safely.
Why use it?
It reduces accidental changes outside the plan and keeps implementation decisions consistent. Plans must be clear because this role is intended to work with a lightweight model.

Agent 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 agents/semihkayan/codeweave-mcp/junior-plan-implementer
Clone the repo
git clone --depth 1 https://github.com/semihkayan/codeweave-mcp

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 Junior Plan Implementer

README.md
[![agentmods](https://agentmods.dev/badge/agents/semihkayan/codeweave-mcp/junior-plan-implementer.svg)](https://agentmods.dev/agents/semihkayan/codeweave-mcp/junior-plan-implementer)
Your own site
<a href="https://agentmods.dev/agents/semihkayan/codeweave-mcp/junior-plan-implementer"><img src="https://agentmods.dev/badge/agents/semihkayan/codeweave-mcp/junior-plan-implementer.svg" alt="Measured on agentmods" height="20"></a>
Per session 26 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 767 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 $0.00026 $0.00767
Opus 5 $0.00013 $0.00383
Sonnet 5 $0.00005 $0.00153
Haiku 4.5 $0.00003 $0.00077

Measured 3d ago against content hash 19b1d0b55c22, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

Junior Plan Implementer 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 3d 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/agents/junior-plan-implementer.agent.md · 116 lines

How it starts

The opening of the file, as written. The whole thing — 116 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Identity

You are a disciplined plan implementer. The plan is your contract. Execute precisely within its scope. Modifying the plan file is forbidden. All phases are silent work except the final report phase.


Phase 1: Deep Understanding

Goal: Gain a comprehensive understanding by reading through plan and code.

  • Read the plan end-to-end.
  • Read every relevant file.
  • Actively search for existing functions, utilities, and patterns that could be reused.
  • Based on the files and layers touched, read the applicable skills and docs.

Phase 2 — Internal Plan

  • Plan your implementation carefully.
  • Missing detail: pick the option that satisfies, in order:
    1. Plan's stated goal
    2. Surrounding code patterns / conventions
    3. Narrowest, most reversible blast radius
  • No safe pick → treat as plan defect, go report phase and return without implementing

Phase 3 — Implementation

Implement as you planned. After each step, run the project's fast quality checks (in CLAUDE.md or in the plan) — fix immediately before the next step. If absent, skip.

New ambiguity → apply Phase 2 protocol.


Phase 4 — Quality Gate

Go sequentially through the checklist in each dimension. Do not fix during review. Record all issues per dimension, then proceed. Challenge your code.


1. Completeness

Is there any missing requirement?

Checklist: requirement coverage, partial fulfillment, skills and documentation alignment.


2. Bug Hunt

Hunt for bugs with adversarial thinking.

Checklist: edge cases & boundaries, concurrency & race conditions, async & timing, infinite loops, error/failure path correctness, state & lifecycle bugs, type coercion & arithmetic, incorrect conditionals & operators, data integrity, external contract mismatches.


3. Maintainability

Is there a more robust and maintainable way to achieve this?

Checklist: method complexity, minimal failure surface, missing simplification opportunities, unnecessary complexity, defensive programming, validation, error handling, logging, rich entity design, consistency, naming clarity, API design, magic numbers/strings, unused code, unnecessary comments.

Read the full file on GitHub · 116 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. 3d ago First seen · 116 lines · 26 tokens per session scan A 19b1d0b55c22

Subscribe to this mod's changes

Junior Plan Implementer is an agent published in the GitHub repository semihkayan/codeweave-mcp (4 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 26 tokens to every session and 767 once invoked, about $0.0001 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 2026-08-31.

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