plan-agent

plan-agent is an agent for coding agents from manti-by/demetra. It costs 0 tokens per session (630 once invoked), scanned A, original, AGPL-3.0.

An agent that investigates a code repository and designs a concrete implementation plan. It does not edit code or run the build.

In plain words
What is it for?
Use it to study a task and repository, choose an approach, and hand the resulting plan to a build agent.
Why use it?
It separates understanding and planning from implementation, so another agent can receive a buildable set of instructions.

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/manti-by/demetra/plan-agent
Clone the repo
git clone --depth 1 https://github.com/manti-by/demetra

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-agent

README.md
[![agentmods](https://agentmods.dev/badge/agents/manti-by/demetra/plan-agent.svg)](https://agentmods.dev/agents/manti-by/demetra/plan-agent)
Your own site
<a href="https://agentmods.dev/agents/manti-by/demetra/plan-agent"><img src="https://agentmods.dev/badge/agents/manti-by/demetra/plan-agent.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 630 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
Origin unknown 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 $0.00000 $0.00630
Opus 5 $0.00000 $0.00315
Sonnet 5 $0.00000 $0.00126
Haiku 4.5 $0.00000 $0.00063

Measured 5d ago against content hash fe15afaf3f07, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

plan-agent scanned grade A with 1 finding 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 5d 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.

Runs shell commandslowCapability

Expected in a hook, worth knowing in a rule or an instructions file.

If you have open questions, list them last as a plain numbered list, one question per line, each ending in `?`. Ask only specific, codebase-answerable questions (e.g. "Should the new retry use the existing `run_command`
.opencode/agents/plan-agent.md · 32 lines

The source is not reproduced here

Licensed AGPL-3.0

The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

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. 5d ago First seen · 32 lines · 0 tokens per session scan A fe15afaf3f07

Subscribe to this mod's changes

plan-agent is an agent published in the GitHub repository manti-by/demetra (7 stars, last pushed 2d ago), licensed AGPL-3.0. It costs nothing until one of its globs matches a file; then it loads 630 tokens. A static security scan graded it A with 1 finding (runs shell commands). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.