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.
npx agentmods add instructions/physicsrob/didah/claude-mdgit clone --depth 1 https://github.com/physicsrob/didahWhat 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 | $0.01186 | $0.01186 |
| Opus 5 | $0.00593 | $0.00593 |
| Sonnet 5 | $0.00237 | $0.00237 |
| Haiku 4.5 | $0.00119 | $0.00119 |
Grade A, and why
didah 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 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.
How it starts
The opening of the file, as written. The whole thing — 113 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Claude Code Configuration
This file contains configuration and context for working with didah using Claude Code.
Project Overview
A modern web application for learning Morse code with real-time feedback, statistics tracking, and multiple study modes. Built with React + TypeScript + Vite, deployed on Cloudflare Pages.
Live App: https://didah.app
Development Commands
# Development
npm run dev # Start Cloudflare dev server (app + API on localhost:3000)
npm run dev:vite # Start Vite only (no API on localhost:5173)
npm test # Run all tests (watch mode)
npm run test:ui # Interactive test UI
npm run build # Build for production
# Quality Checks (run these before committing!)
npm run check # Run ALL checks: TypeScript, ESLint, and tests
npm run check:fix # Same as check but auto-fix lint issues
npm run typecheck # TypeScript type checking only
npm run lint # ESLint only
# Deployment
# Note: Cloudflare Pages automatically builds and deploys on git push
npm run deploy # Manual deployment (alternative to automatic)
Architecture
- Core Domain:
src/core/- Timing engine, alphabet, types - Runtime System:
src/features/session/runtime/- Session orchestration - Modes:
src/features/session/modes/- Mode implementations (Letter Practice, Listen, Live Copy, Head Copy, Dit Dash) - Services:
src/features/session/services/- Audio, feedback - Pages:
src/pages/- React components - API Functions:
functions/api/- Cloudflare Pages Functions
Styling Approach
IMPORTANT: This project uses regular CSS files with class names. We do NOT use Tailwind CSS.
- Style files are in
src/styles/and component-specific CSS files - Main styles:
src/styles/main.css(CSS variables, base styles) - Component styles:
src/components/ComponentName.css - Page styles:
src/styles/pageName.css - Write semantic class names, not utility classes
- Use the CSS variables defined in main.css for colors and spacing
- See
brand.mdfor design guidelines
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.
- yesterday First seen · 113 lines · 1,186 tokens per session scan A 9499216be139
didah CLAUDE.md is an instructions file published in the GitHub repository physicsrob/didah (2 stars, last pushed 9mo ago), licensed MIT. It adds 1,186 tokens to every session, about $0.0059 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.
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