prospero CLAUDE.md

prospero CLAUDE.md is an instructions file for coding agents from bguthrie/prospero. It costs 1,565 tokens per session, scanned A, original, MIT.

Repository instructions for Prospero, a Claude Code plugin made from Markdown and TOML files rather than a running application. They describe its four-stage content pipeline and its manifest, presets, templates, and validation script.

In plain words
What is it for?
Use them when editing Prospero commands, skills, content-management presets, templates, manifests, or running its static validation check.
Why use it?
They explain how the plugin is structured and how to check structural changes. This prevents treating prompts as ordinary application code or expecting a build system and test runner that do not exist.

Instructions file

Installs and runs on its own, but its text points at files inside the plugin that ships it — anything it tells you to read at a ${CLAUDE_PLUGIN_ROOT} path is only there once the plugin is installed.

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 instructions/bguthrie/prospero/claude-md
Clone the repo
git clone --depth 1 https://github.com/bguthrie/prospero

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 prospero CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/bguthrie/prospero/claude-md.svg)](https://agentmods.dev/instructions/bguthrie/prospero/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/bguthrie/prospero/claude-md"><img src="https://agentmods.dev/badge/instructions/bguthrie/prospero/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,565 This file is loaded in full into every session.
When invoked 1,565 The same file — it is already loaded in full.
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 $0.01565 $0.01565
Opus 5 $0.00783 $0.00783
Sonnet 5 $0.00313 $0.00313
Haiku 4.5 $0.00156 $0.00156

Measured 4d ago against content hash 797d78ee70e6, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

prospero CLAUDE.md 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 4d 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.

CLAUDE.md · 91 lines

How it starts

The opening of the file, as written. The whole thing — 91 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

What this repository is

Prospero is a Claude Code plugin (not an application). There is no build step, runtime, or package manager. The "code" is markdown and TOML: command shims, skill prompts, CMS presets, and rubric templates. Claude Code loads everything at runtime from the plugin root.

Plugin manifest: .claude-plugin/plugin.json. Marketplace entry: .claude-plugin/marketplace.json.

Commands

The only automated check is a static lint:

./tests/validate.sh

It verifies the manifest parses, the required skills/commands/presets/templates exist, each preset has its required keys (posts_dir, post_path_pattern, drafts_dir, frontmatter_template), and every SKILL.md has name: and description: frontmatter. Run it after any structural change.

There is no test runner for skill behavior — skills are LLM prompts, not code. tests/fixtures/hugo/{before,after}/ shows the expected filesystem state around /init; examples/sample-post/ shows per-phase artifacts for a single post.

Architecture

The four-phase pipeline

interrogate → critique → author → revise. Each phase is one skill that does one job and produces one artifact; phases communicate via files on disk, not conversation state. The prospero skill is a router that picks a phase from user intent; it does not chain phases or duplicate their preflight checks. Each phase decides its own handoff (e.g., /interrogate auto-invokes /critique; /critique does NOT auto-invoke /author — the author must accept the critique first).

Cross-phase state is files, keyed by slug:

  • Outline: <drafts_dir>/<slug>/outline.md — written by interrogate, read by critique/author.
  • Research: <drafts_dir>/<slug>/research.md — the accumulating research record for the post. Interrogate initializes it, critique extends it (and consumes it before doing new web calls — research is not re-derived), author expands it while grounding the draft. Every writer appends under a YYYY-MM-DDTHH:MM section header (local time, to the minute) so multiple same-day passes do not collide. Never overwritten.
  • Post: resolved post_path_pattern — written by author, edited by revise.

Read the full file on GitHub · 91 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. 4d ago First seen · 91 lines · 1,565 tokens per session scan A 797d78ee70e6

Subscribe to this mod's changes

prospero CLAUDE.md is an instructions file published in the GitHub repository bguthrie/prospero (6 stars, last pushed 3mo ago), licensed MIT. It adds 1,565 tokens to every session, about $0.0078 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.