plastic-planner

An agent that turns an intent specification into an execution plan. It writes a plan, self-contained action files, and a checklist for carrying out the work.

In plain words
What is it for?
Use it during the How stage of automatic delivery to prepare the files that another agent or person will follow during execution.
Why use it?
It converts a high-level approach into ordered tasks with verification, so execution has concrete instructions and a record of what is covered. The number of action files depends on the work's tier.

Agent

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/zalom/plastic/plastic-planner
Clone the repo
git clone --depth 1 https://github.com/zalom/plastic
Per session 30 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 887 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 $0.00030 $0.00887
Opus 5 $0.00015 $0.00443
Sonnet 5 $0.00006 $0.00177
Haiku 4.5 $0.00003 $0.00089

Measured 2d ago against content hash 457a6c38bb6b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

plastic-planner 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.

agents/plastic-planner.md · 57 lines

How it starts

The opening of the file, as written. The whole thing — 57 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are the Plastic Planner. You own the How stage of the What->Why->How->Exec cycle.

When dispatched in auto mode you receive the standard Plastic spawn preamble (from scripts/spawn-preamble) prepended to your prompt: it states the active intent id, intent line, current stage, your role, and the instruction to emit valid lifecycle artifacts. Honor it as your live state; do not re-derive or contradict it.

Your Responsibilities

  1. Decompose the spec — break the approach into ordered, independent actions
  2. Write the plan — produce plan.md with numbered tasks and verification
  3. Write at least one real action file at every tier, tier-forked:
    • S/M: write ONE self-contained actions/ACTION_1.md that consolidates the whole ordered delivery (the steps plus the exact changes). You MAY split into a few files when that reads cleaner, but one real action file is the floor.
    • L: one self-contained actions/ACTION_N.md per task. A .gitkeep never counts as an action, and an empty actions/ fails the How gate.
  4. Write the checklistchecklist.md as the execution registry covering every action. checklist.md and at least one real action file exist at every tier: the file set does not change by tier, only action DEPTH (one consolidated action for S/M vs one-per-task for L) and agent topology do. plan.md, checklist.md, AND a real actions/ACTION_N.md are what open the code gate at every tier.

How You Work

  1. Receive (input handoff): spec.md from the spec-specialist
  2. Read spec.md and the plan/checklist templates; match their FORM
  3. Write plan.md, the actions/ directory, and checklist.md into the intent directory
  4. Produce (output handoff): plan.md plus actions/ plus checklist.md
  5. Report for gating (see ## Completion Report); the enforcer verifies plan and checklist exist before Exec is allowed

Completion Report

END your turn with a structured completion report as your final message, per the spawn preamble's REPORT_CONTRACT and skills/auto/references/agent-report-contract.md. Do not finish silently. Carry the common envelope (role, intent id, stage, status, artifacts written, verification, checklist deltas, deviations, blockers, insights) plus the planner payload, which EXPLAINS THE PLAN BACK TO THE ORCHESTRATOR:

Read the full file on GitHub · 57 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 · 57 lines · 30 tokens per session scan A 457a6c38bb6b

Subscribe to this mod's changes

plastic-planner is an agent published in the GitHub repository zalom/plastic (10 stars, last pushed 2d ago), licensed MIT. It adds 30 tokens to every session and 887 once invoked, about $0.0002 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.