An XML-based language and development environment for defining and testing structured AI behaviours in Claude Code.

It helps create and test structured AI behaviour components, while enforcing document references and comment formatting.

It provides rules for keeping generated documents consistent, such as avoiding copied content and using clear XML comments.

How apiksdev/axel-core configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to apiksdev/axel-core. 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/apiksdev/axel-core/master/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/apiksdev/axel-core

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/apiksdev/axel-core/claude-md/github.svg)](https://agentmods.dev/instructions/apiksdev/axel-core/claude-md)

Your own site

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

Per session 467 This file is loaded in full into every session.

When invoked 467 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	$0.00467	$0.00467
Opus 5.5	$0.00187	$0.00187
Sonnet 5.5	$0.00093	$0.00093
Haiku 4.5	$0.00047	$0.00047

Measured 2mo ago against content hash a7449569cd65, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

axel-plugin 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 · 60 lines

What it actually says

AXEL Plugin

<document type="project">

  <enforcement>
    <![CDATA[
    ⛔ CONTENT DUPLICATION RULES
    - ❌ NEVER copy content from referenced documents into new documents
    - Referenced documents are already loaded via context or on-demand loading
    - New documents should only contain unique, non-duplicated information
    - Reference existing content via <read src=".."/> in <documents> block
    - If content exists elsewhere → reference it, do not duplicate it

    ⛔ XML COMMENT FORMAT RULES
    - ❌ NEVER use multi-line decorative comments
    - ❌ NEVER use box-style comments with separator lines (====, ----, ****)
    - ❌ NEVER use comments like: <!-- ========== SECTION ========== -->
    - ✅ ALWAYS use single-line format: <!-- stage_id: Description -->
    - Comment must be placed directly before the element it describes
    ]]>
  </enforcement>

  <project name="axel-plugin" version="1.0.1">
    <description>
       AXEL (AI XML Execution Language) development environment for creating and testing
      structured AI behavior components. AXEL is an XML-based DSL plugin for Claude Code
      that addresses inconsistent AI behavior through enforceable instructions that persist
      across sessions. This project serves as the development workspace for building AXEL
      components including Skills (specialized AI expertise), Agents (autonomous task executors),
      Workflows (multi-step processes), Commands (slash command definitions), Todos (task management),
      and Memory systems (cross-session context persistence).
    </description>
    <stack>
      - language: XML, Markdown, YAML
      - platform: Claude Code
      - type: DSL (Domain-Specific Language)
    </stack>
  </project>
  
  <locale default="en">
    - code: en
    - docs: en
    - communication: tr
    - commits: en
    - todos: tr
  </locale>
  
  <understanding/>
  
</document>

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 · 60 lines · 467 tokens per session scan A a7449569cd65

Subscribe to this mod's changes

axel-plugin is an instructions file published in the GitHub repository apiksdev/axel-core (7 stars, last pushed 9mo ago), licensed Apache-2.0. It adds 467 tokens to every session, about $0.0019 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.

Building agents

axel-plugin next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
axel-pluginapiksdev/axel-core	Instructions file	7	9mo ago	Apache-2.0	A	467	Claude Code
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	today	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	today	MIT	A	4,680	Codex, OpenCode
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
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	275k	2d ago	MIT	A	4,313	Codex, OpenCode

axel-core: Instructions file for Claude Code