plan

plan is an agent for coding agents from gf-labs/claude-toolbox. It costs 19 tokens per session (285 once invoked), scanned A, original, MIT.

A read-only planning agent that examines a codebase and returns a phase-by-phase implementation plan.

In plain words
What is it for?
It is for exploring a repository and preparing a structured plan without modifying files.
Why use it?
It helps break a software change into manageable phases while identifying files, reusable code, dependencies, and verification steps before coding begins.

Agent

Part of the tools plugin — 2 skills, 13 commands, 5 agents, 4 hooks shipped together

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/gf-labs/claude-toolbox/plan
Clone the repo
git clone --depth 1 https://github.com/gf-labs/claude-toolbox

Or install tools, the plugin that ships this one along with the rest of its 2 skills, 13 commands, 5 agents, 4 hooks.

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 plan

README.md
[![agentmods](https://agentmods.dev/badge/agents/gf-labs/claude-toolbox/plan.svg)](https://agentmods.dev/agents/gf-labs/claude-toolbox/plan)
Your own site
<a href="https://agentmods.dev/agents/gf-labs/claude-toolbox/plan"><img src="https://agentmods.dev/badge/agents/gf-labs/claude-toolbox/plan.svg" alt="Measured on agentmods" height="20"></a>
Per session 19 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 285 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 $0.00019 $0.00285
Opus 5 $0.00010 $0.00143
Sonnet 5 $0.00004 $0.00057
Haiku 4.5 $0.00002 $0.00028

Measured 3d ago against content hash e4aee0fed1be, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

plan 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.

agents/plan.md · 36 lines

What it actually says

You are an implementation planning agent. Explore the codebase thoroughly, then return a structured phase-by-phase implementation plan. Do NOT modify any files.

Process

  1. Understand the request fully before planning
  2. Use Glob and Grep to locate relevant files; use Read to understand existing patterns
  3. Identify existing utilities and functions to reuse — avoid proposing new code when something already fits
  4. Divide the work into logical phases (1–4 is typical; more only if genuinely needed)

Output format

Start with a one-paragraph Context section explaining what the change does and why.

Then for each phase:

Phase N — [Goal in one sentence]

  • Files to create: [list, or "none"]
  • Files to modify: [list with brief note on what changes]
  • Existing code to reuse: [function/class @ file:line, or "none"]
  • Depends on: [Phase N, or "none"]

End with:

Verification

  • [step-by-step: how to run/test each phase and confirm it worked]

Keep it scannable — one screen if possible. Skip phases that aren't needed.

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 · 36 lines · 19 tokens per session scan A e4aee0fed1be

Subscribe to this mod's changes

plan is an agent published in the GitHub repository gf-labs/claude-toolbox (2 stars, last pushed 1mo ago), licensed MIT. It adds 19 tokens to every session and 285 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.