What is flashy CLAUDE.md?

A project instruction file for Claude Code, containing background about the Flashy plugin, its structure, commands, and testing process.

Use it when working on Flashy, a Bash plugin that changes the terminal background when Claude finishes or needs attention.

It gives the coding agent the repository context needed to make compatible changes and run the right checks.

How foundinblank/flashy configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to foundinblank/flashy. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/foundinblank/flashy/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/foundinblank/flashy

Made for: Claude Code.

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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/foundinblank/flashy/claude-md/github.svg)](https://agentmods.dev/instructions/foundinblank/flashy/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/foundinblank/flashy/claude-md"><img src="https://agentmods.dev/badge/instructions/foundinblank/flashy/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/foundinblank/flashy/claude-md"><img src="https://agentmods.dev/badge/instructions/foundinblank/flashy/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 950 This file is loaded in full into every session.

When invoked 950 The same file — it is already loaded in full.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

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.

Model	Per session	Once invoked
Fable 5.1	$0.00950	$0.00950
Opus 5.5	$0.00380	$0.00380
Sonnet 5.5	$0.00190	$0.00190
Haiku 4.5	$0.00095	$0.00095

Measured 2mo ago against content hash 94356efaf888, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

flashy 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 2mo 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 · 56 lines

How it starts

The opening of the file, as written. The whole thing — 56 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.

Project Overview

Flashy is a Claude Code plugin written in pure Bash that pulses the terminal background color when Claude finishes a turn (Stop event) or sends a notification. It has zero external dependencies.

Architecture

.claude-plugin/plugin.json — Plugin metadata (name, version, author)
hooks/hooks.json — Registers two Claude Code hook events (Stop, Notification), each calling flash.sh with the event name as $1. Notification is narrowed to matcher: "permission_prompt|idle_prompt|agent_needs_input"; both entries carry a 2-second timeout so a hung hook can't stall Claude Code.
hooks/flash.sh — The entire implementation in one script:
1. Sources user config from ${XDG_CONFIG_HOME:-$HOME/.config}/flashy/config (if it exists), then applies bash parameter expansion defaults
2. For stop, if stdin isn't a TTY, reads the hook's JSON and suppresses the pulse when Claude Code (v2.1.145+) reports non-empty background_tasks or session_crons — see "Stop Suppression" below
3. Detects terminal background color via three-tier cascade: per-TTY color file → OSC 11 terminal query → static FALLBACK_COLOR
4. Computes adaptive flash color by measuring luminance and shifting RGB toward white (dark themes) or black (light themes)
5. Runs a pulse loop: set bg to flash color via OSC 11, sleep, restore original bg
config.default — Reference template for user config; not read at runtime
DESIGN.md — Detailed technical design document
tests/test_flash_stop_suppression.sh — Pure-bash automated test suite for the stop-suppression logic

Commands

No build system or linter. There is a pure-bash test suite for the stop-suppression logic, plus manual testing for the rest:

# Run the automated test suite (no jq/python/node required)
./tests/test_flash_stop_suppression.sh

# Test flash directly (must be run in a supported terminal, not VS Code)
./hooks/flash.sh stop
./hooks/flash.sh notification

# Install as Claude Code plugin
claude plugin add /path/to/flashy

Read the full file on GitHub · 56 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.

2mo ago First seen · 56 lines · 950 tokens per session scan A 94356efaf888

Subscribe to this mod's changes

flashy CLAUDE.md is an instructions file published in the GitHub repository foundinblank/flashy (2 stars, last pushed 3mo ago), licensed MIT. It adds 950 tokens to every session, about $0.0038 per session on Opus 5.5. 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.

flashy CLAUDE.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
flashy CLAUDE.mdfoundinblank/flashy	Instructions file	2	3mo ago	MIT	A	950	Claude Code
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vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	3,093	GitHub Copilot
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flashy: Instructions file for Claude Code