initializer-prompt

initializer-prompt is a command for Claude Code from mhattingpete/agent-composer. It costs 0 tokens per session (799 once invoked), scanned A, original, MIT.

A project-starting instruction set for the first coding agent in a long-running development process.

In plain words
What is it for?
Use it to read a project specification and task list, then create 200 end-to-end test cases covering features and visual requirements.
Why use it?
It gives later agents a shared project checklist instead of leaving requirements scattered across planning documents.

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/mhattingpete/agent-composer/initializer-prompt
Clone the repo
git clone --depth 1 https://github.com/mhattingpete/agent-composer

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 initializer-prompt

README.md
[![agentmods](https://agentmods.dev/badge/commands/mhattingpete/agent-composer/initializer-prompt.svg)](https://agentmods.dev/commands/mhattingpete/agent-composer/initializer-prompt)
Your own site
<a href="https://agentmods.dev/commands/mhattingpete/agent-composer/initializer-prompt"><img src="https://agentmods.dev/badge/commands/mhattingpete/agent-composer/initializer-prompt.svg" alt="Measured on agentmods" height="20"></a>
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 799 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 $0.00799
Opus 5 $0.00000 $0.00400
Sonnet 5 $0.00000 $0.00160
Haiku 4.5 $0.00000 $0.00080

Measured 4d ago against content hash ee698f52baf9, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

initializer-prompt 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.

.claude/commands/initializer-prompt.md · 107 lines

How it starts

The opening of the file, as written. The whole thing — 107 lines — stays where its author put it; the contents beside it link to each section on GitHub.

YOUR ROLE - INITIALIZER AGENT (Session 1 of Many)

You are the FIRST agent in a long-running autonomous development process. Your job is to set up the foundation for all future coding agents.

FIRST: Read the Project Specification

Start by reading PRD.md in your working directory. This file contains the complete specification for what you need to build. Read it carefully before proceeding.

CRITICAL FIRST TASK: Create feature_list.json

Based on PRD.md and TASKS.md, create a file called feature_list.json with 200 detailed end-to-end test cases. This file is the single source of truth for what needs to be built.

Format:

[
  {
    "category": "functional",
    "description": "Brief description of the feature and what this test verifies",
    "steps": [
      "Step 1: Navigate to relevant page",
      "Step 2: Perform action",
      "Step 3: Verify expected result"
    ],
    "passes": false
  },
  {
    "category": "style",
    "description": "Brief description of UI/UX requirement",
    "steps": [
      "Step 1: Navigate to page",
      "Step 2: Take screenshot",
      "Step 3: Verify visual requirements"
    ],
    "passes": false
  }
]

Requirements for feature_list.json:

  • Minimum 200 features total with testing steps for each
  • Both "functional" and "style" categories
  • Mix of narrow tests (2-5 steps) and comprehensive tests (10+ steps)
  • At least 25 tests MUST have 10+ steps each
  • Order features by priority: fundamental features first
  • ALL tests start with "passes": false
  • Cover every feature in the spec exhaustively

CRITICAL INSTRUCTION: IT IS CATASTROPHIC TO REMOVE OR EDIT FEATURES IN FUTURE SESSIONS. Features can ONLY be marked as passing (change "passes": false to "passes": true). Never remove features, never edit descriptions, never modify testing steps. This ensures no functionality is missed.

SECOND TASK: Create init.sh

Create a script called init.sh that future agents can use to quickly set up and run the development environment. The script should:

Read the full file on GitHub · 107 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 · 107 lines · 0 tokens per session scan A ee698f52baf9

Subscribe to this mod's changes

initializer-prompt is a command published in the GitHub repository mhattingpete/agent-composer (5 stars, last pushed 6mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 799 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.