plan

A command for building an architecture plan or an execution plan and saving it to a project file.

In plain words
What is it for?
Turning feature requirements into an `ARCHITECTURE.md` file, or turning an existing architecture document into `PLANNER_EXECUTION.md`. It does not carry out the plan.
Why use it?
It separates planning from implementation and keeps the complete plan in a file instead of duplicating it in chat.

Command

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/spumer/i-m-senior-developer/plan
Clone the repo
git clone --depth 1 https://github.com/spumer/i-m-senior-developer
Per session 15 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 357 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 $0.00015 $0.00357
Opus 5 $0.00008 $0.00179
Sonnet 5 $0.00003 $0.00071
Haiku 4.5 $0.00002 $0.00036

Measured 2d ago against content hash b1252b5f9cbc, 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 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.

plugins/planner/commands/plan.md · 25 lines

What it actually says

Activate the planner skill and follow its workflow start-to-finish.

Interpret $ARGUMENTS as follows:

  • A path to a feature README.md, or a feature directory containing that file, runs Mode 1 (architecture) and writes ARCHITECTURE.md beside the README.
  • A path to an existing architecture document (*-PLAN-*.md, *-DESIGN-*.md, ARCHITECTURE.md, or an explicitly supplied equivalent) runs Mode 2 (execution) and writes PLANNER_EXECUTION.md beside that document.
  • Free text with no readable path runs Mode 1 (architecture) and writes .claude/plans/<task-slug>/ARCHITECTURE.md under the project root.

A successful run always writes the full result to its target file. Chat output after a successful write contains only:

  1. the result kind;
  2. the file path and version;
  3. two to four main outcomes;
  4. the next command, when another step is required.

Never duplicate the full plan in chat after a successful write. If writing the file or synchronizing its metadata fails, state that the result was not saved and emit the complete prepared document to chat as the fallback result.

Do not execute the plan and do not start implementation agents. Use the state helper exactly as described by the skill to synchronize versions and detect stale execution plans.

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 · 25 lines · 15 tokens per session scan A b1252b5f9cbc

Subscribe to this mod's changes

plan is a command published in the GitHub repository spumer/i-m-senior-developer (11 stars, last pushed 11d ago), licensed MIT. It adds 15 tokens to every session and 357 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.