# How the improve-claude-md Skill Works with CLAUDE.md Files: A Complete Guide

> Discover how the improve-claude-md skill enhances CLAUDE.md files by wrapping instructions in XML tags for precise Claude Code guidance. Learn to improve your development workflow.

- Repository: [HumanLayer/skills](https://github.com/humanlayer/skills)
- Tags: how-to-guide
- Published: 2026-09-12

---

**The improve-claude-md skill rewrites CLAUDE.md files by wrapping condition-specific instructions in `<important if="...">` XML tags, enabling Claude Code to identify and follow relevant guidance with precision during development tasks.**

The `improve-claude-md` skill from the `humanlayer/skills` repository addresses a critical limitation in AI-assisted development: static project documentation often gets ignored because the model cannot determine which sections apply to the current task. By transforming flat markdown into a structured, condition-tagged format, the skill ensures that Claude Code receives clear relevance signals for every piece of project context.

## Core Processing Algorithm

According to the skill definition in [`plugins/improve-claude-md/skills/improve-claude-md/SKILL.md`](https://github.com/humanlayer/skills/blob/main/plugins/improve-claude-md/skills/improve-claude-md/SKILL.md), the tool executes a five-step transformation pipeline when processing a CLAUDE.md file:

### 1. Isolate Foundational Context

The skill preserves the project identity, tech-stack summary, and project map as plain markdown at the top of the file. These sections remain always-visible because they provide essential orientation that applies to every interaction.

### 2. Wrap Command Tables

Every command from the original documentation is collected and placed inside a single `<important if="you need to run commands to build, test, lint, or generate code">` block. This signals to Claude that the enclosed table is relevant specifically when performing build, test, or generation tasks.

### 3. Fragment Rule Lists

Generic "Coding Standards" sections are split into individual rules, with each rule placed in its own `<important if>` block featuring a narrow condition. For example, a rule about imports receives the condition `"you are adding or modifying imports or exports"`, giving Claude a precise trigger for when that specific instruction matters.

### 4. Separate Domain Sections

Knowledge domains like testing patterns, API conventions, state management, and internationalization each receive dedicated `<important if>` blocks. The condition describes the specific scenario where that domain knowledge applies, such as `"you are writing or modifying tests"` or `"you are working with state management"`.

### 5. Prune Linter-Only Content

The skill removes style guidelines enforceable by linters (e.g., camelCase rules), stale code snippets, and vague best-practice statements. Instead, it encourages replacing these with references to pre-commit hooks or specific file paths, keeping the CLAUDE.md focused on architectural decisions and project-specific workflows that automated tools cannot enforce.

## The `<important if>` XML Tag Structure

The transformation relies on custom XML tags that provide explicit relevance signals. Unlike generic markdown sections, these tags tell Claude exactly when the enclosed content applies.

The syntax follows this pattern:

```markdown
<important if="[specific condition describing when this applies]">
- Instruction 1
- Instruction 2
</important>

```

Conditions use natural language descriptions of the programming context, such as:
- `"you are adding or modifying imports or exports"`
- `"you are creating new components"`
- `"you are adding or modifying API routes"`

This approach overrides the default system reminder that sections "may or may not be relevant" with a definitive signal about applicability.

## Transformation Example: Before and After

Here is how the skill processes a typical CLAUDE.md file from the repository examples.

**Before improvement:**

```markdown

# CLAUDE.md

This is an Express API with a React frontend in a Turborepo monorepo.

## Commands

| Command | Description |
|---|---|
| `turbo build` | Build all packages |
| `turbo test` | Run all tests |
| `turbo lint` | Lint all packages |
| `turbo dev` | Start dev server |

## Coding Standards

- Use named exports
- Use functional components with TypeScript interfaces for props
- Use camelCase for variables, PascalCase for components

```

**After running the improve-claude-md skill:**

```markdown

# CLAUDE.md

Express API + React frontend in a Turborepo monorepo.

## Project map

- `apps/api/` - Express REST API
- `apps/web/` - React SPA

<important if="you need to run commands to build, test, lint, or generate code">
| Command | What it does |
|---|---|
| `turbo build` | Build all packages |
| `turbo test` | Run all tests |
| `turbo lint` | Lint all packages |
| `turbo dev` | Start dev server |
</important>

<important if="you are adding or modifying imports or exports">
- Use named exports (no default exports)
</important>

<important if="you are creating new components">
- Use functional components with TypeScript interfaces for props
</important>

```

Notice the removal of the linter-enforceable casing guidelines and the transformation of generic standards into condition-specific alert blocks.

## Source Files and Implementation

The skill is defined by two primary files in the `humanlayer/skills` repository:

- **[`plugins/improve-claude-md/skills/improve-claude-md/SKILL.md`](https://github.com/humanlayer/skills/blob/main/plugins/improve-claude-md/skills/improve-claude-md/SKILL.md)**: Contains the full processing algorithm, transformation logic, and specification for how content should be restructured and tagged.

- **[`plugins/improve-claude-md/.claude-plugin/plugin.json`](https://github.com/humanlayer/skills/blob/main/plugins/improve-claude-md/.claude-plugin/plugin.json)**: Registers the skill with the Claude plugin system, defining metadata such as the skill name, description, and entry point for invocation.

These files implement the parsing logic that identifies command tables, splits rule lists, and generates the conditional XML wrappers.

## Summary

- The **improve-claude-md skill** transforms static CLAUDE.md files into dynamic instruction sets using `<important if>` XML tags.
- **Condition-specific wrapping** ensures Claude Code knows exactly when each rule, command, or pattern applies to the current task.
- **Command tables** are consolidated into single blocks triggered by build, test, or generation contexts.
- **Linter-only rules** and vague best practices are pruned to reduce noise and prevent redundancy with automated tooling.
- The source specification resides in [`SKILL.md`](https://github.com/humanlayer/skills/blob/main/SKILL.md) within the `humanlayer/skills` repository.

## Frequently Asked Questions

### What does the improve-claude-md skill do?

The skill parses an existing CLAUDE.md file and restructures it to improve Claude Code's instruction adherence. It extracts core project information, preserves command references, fragments broad rule lists into specific conditional blocks, and removes content that linters already enforce.

### How do `<important if>` tags improve Claude Code performance?

These XML tags provide explicit relevance signals that tell Claude exactly when a specific instruction applies. Instead of scanning generic sections that "may or may not be relevant," Claude receives targeted context tied to specific development activities like modifying imports or writing tests, reducing the likelihood of ignoring critical guidance.

### What content gets removed during the improvement process?

The skill removes style guidelines enforceable by linters (such as naming conventions), stale code snippets, and vague best-practice statements. It preserves architectural decisions, project-specific workflows, testing patterns, and essential commands that require human judgment or project-specific context.

### Where is the improve-claude-md skill defined?

The complete specification and transformation algorithm are defined in [`plugins/improve-claude-md/skills/improve-claude-md/SKILL.md`](https://github.com/humanlayer/skills/blob/main/plugins/improve-claude-md/skills/improve-claude-md/SKILL.md) within the `humanlayer/skills` GitHub repository, with plugin registration metadata located at [`plugins/improve-claude-md/.claude-plugin/plugin.json`](https://github.com/humanlayer/skills/blob/main/plugins/improve-claude-md/.claude-plugin/plugin.json).