prep

A session-start command that loads the architecture rules relevant to the task, such as project, language, or domain guidance.

In plain words
What is it for?
Use it before coding to identify the task's scope, load matching rules, and review any project architecture file.
Why use it?
It reduces the chance of writing code that conflicts with the project's existing design rules. It also flags when the work moves outside the agreed scope.

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/ackeskin/contexture/prep
Clone the repo
git clone --depth 1 https://github.com/AcKeskin/contexture
Per session 24 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 293 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 $0.00024 $0.00293
Opus 5 $0.00012 $0.00147
Sonnet 5 $0.00005 $0.00059
Haiku 4.5 $0.00002 $0.00029

Measured yesterday against content hash c13df3006845, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

prep 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 yesterday.

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.

commands/prep.md · 18 lines

What it actually says

Run the prep skill for the current task.

Any text after /prep is treated as scope hints that bias scope detection. Examples:

  • /prep — infer scope from the current task + project.
  • /prep typescript ui-components — prime for TypeScript UI work explicitly.
  • /prep cpp rendering — prime for C++ rendering work, overriding cwd-based inference.

The skill identifies task scope (language, domain, project, task type), calls skills/discover/SKILL.md with kind: "architectural-rule" and render_bodies: true, merges and caps the result (project > domain > language > universal; ≤ 20 rules; <500 tokens), reads .claude/architecture.md if present, and surfaces the priming block with the loaded rules so you can confirm the scope is right.

Prep also auto-fires on first substantive task of a session, first task after /clear, and when the user signals a topic shift. During subsequent work it observes drift and asks before proceeding outside the primed scope — never silently. On user push-back ("you violated rule X"), prep proposes a capture via /capture rather than writing directly.

See ~/.claude/skills/prep/SKILL.md for the full procedure.

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. yesterday First seen · 18 lines · 24 tokens per session scan A c13df3006845

Subscribe to this mod's changes

prep is a command published in the GitHub repository AcKeskin/contexture (2 stars, last pushed 1mo ago), licensed MIT. It adds 24 tokens to every session and 293 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.