Borrowing it
Nothing to install: this file belongs to amitshekhariitbhu/language-experiments. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/amitshekhariitbhu/language-experiments/main/CLAUDE.mdgit clone --depth 1 https://github.com/amitshekhariitbhu/language-experimentsWrote 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.
[](https://agentmods.dev/instructions/amitshekhariitbhu/language-experiments/claude-md)<a href="https://agentmods.dev/instructions/amitshekhariitbhu/language-experiments/claude-md"><img src="https://agentmods.dev/badge/instructions/amitshekhariitbhu/language-experiments/claude-md.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00633 | $0.00633 |
| Opus 5 | $0.00316 | $0.00316 |
| Sonnet 5 | $0.00127 | $0.00127 |
| Haiku 4.5 | $0.00063 | $0.00063 |
Grade A, and why
language-experiments 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 7d 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.
How it starts
The opening of the file, as written. The whole thing — 53 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.
Purpose
This is a language experimentation project. The goal is to explore programming languages through hands-on experiments that reveal non-obvious, unique, or surprising behaviors — things you don't learn from textbooks.
How It Works
When the user asks to do a new experiment (e.g., "do a new experiment in Python" or "new experiment in Kotlin on coroutines"):
- Read all existing experiment files and
INSIGHTS.mdin the<language>/folder to understand what's already covered. - If the user specified a topic, create an experiment on that topic (but still avoid repeating existing insights).
- If no topic specified, pick a topic that is NOT already covered by existing experiments.
- Create the experiment as a standalone, runnable script in
<language>/. - Run the experiment and capture actual output.
- Append the new insight to
<language>/INSIGHTS.md.
If the language folder doesn't exist yet, create it.
Rules for Experiments
- No web apps, no frameworks — pure language experiments only.
- Each experiment file should be self-contained and runnable independently.
- Name experiments descriptively:
floating_point_trap.py,mutable_default_gotcha.py, etc. - Every experiment must include comments explaining what's happening and why it's surprising.
- Focus on behaviors that differ from other languages or defy common assumptions.
- Run the experiments and capture actual output in INSIGHTS.md.
- Never repeat an experiment or insight that already exists in the language folder.
Running Experiments
- C:
gcc -std=c17 -o /tmp/c_exp c/<file>.c && /tmp/c_exp - C++:
g++ -std=c++17 -o /tmp/cpp_exp cpp/<file>.cpp && /tmp/cpp_exp - Go:
go run go/<file>.go - Java:
javac java/<file>.java -d /tmp/java_exp && java -cp /tmp/java_exp <ClassName> - JavaScript:
node javascript/<file>.js - Kotlin:
kotlinc kotlin/<file>.kt -include-runtime -d /tmp/kt_exp.jar && java -jar /tmp/kt_exp.jar - Python:
python3 python/<file>.py - Ruby:
ruby ruby/<file>.rb - Rust:
rustc rust/<file>.rs -o /tmp/rust_exp && /tmp/rust_exp - Swift:
swiftc swift/<file>.swift -o /tmp/swift_exp && /tmp/swift_exp - Other languages: use standard toolchain for that language.
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.
- 7d ago First seen · 53 lines · 633 tokens per session scan A 70ee8c9bd594
language-experiments CLAUDE.md is an instructions file published in the GitHub repository amitshekhariitbhu/language-experiments (10 stars, last pushed 6mo ago), licensed MIT. It adds 633 tokens to every session, about $0.0032 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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