build-claude-code: Instructions file for Claude Code

CLAUDE.md

build-claude-code CLAUDE.md is an instructions file for Claude Code from OPBR/build-claude-code. It costs 2,206 tokens per session, scanned A, original, no licence file.

A set of instructions for the OPBR/build-claude-code project, which explains how to build an AI coding agent from the beginning. It includes the project overview, technology choices, learning path, and folder structure.

In plain words
What is it for?
Use it when working on OPBR/build-claude-code or learning from its documented technology stack, development path, and directory structure.
Why use it?
It gives contributors project-specific guidance so they can understand how the project is organised and how its build approach is described.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md.

This is OPBR/build-claude-code's own configuration. It tells Claude Code how to work on build-claude-code itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything build-claude-code configures →

Reuse

Borrowing it

Nothing to install: this file belongs to OPBR/build-claude-code. 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/OPBR/build-claude-code/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/OPBR/build-claude-code

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.

agentmods badge for build-claude-code CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/opbr/build-claude-code/claude-md/github.svg)](https://agentmods.dev/instructions/opbr/build-claude-code/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/opbr/build-claude-code/claude-md"><img src="https://agentmods.dev/badge/instructions/opbr/build-claude-code/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.

agentmods 80×15 button for build-claude-code CLAUDE.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/opbr/build-claude-code/claude-md"><img src="https://agentmods.dev/badge/instructions/opbr/build-claude-code/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 2,206 This file is loaded in full into every session.
When invoked 2,206 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 unknown 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 5.1 $0.02206 $0.02206
Opus 5.5 $0.00882 $0.00882
Sonnet 5.5 $0.00441 $0.00441
Haiku 4.5 $0.00221 $0.00221

Measured 1mo ago against content hash d58c5d621483, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

build-claude-code 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 1mo 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 · 210 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 1mo ago Changed · +6 lines · +106 tokens per session d58c5d621483
  2. 1mo ago First seen · 204 lines · 2,100 tokens per session scan A e90110352fb5

Subscribe to this mod's changes

build-claude-code CLAUDE.md is an instructions file published in the GitHub repository OPBR/build-claude-code (137 stars, last pushed 1mo ago), with no licence file. It adds 2,206 tokens to every session, about $0.0088 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 2026-08-30.

Related

Other instructions, from other repositories