How to Test Local Plugin Changes by Copying into Claude Code's Plugin Cache

You can test local changes to the Understand-Anything plugin by building the packages, deleting the cached version at ~/.claude/plugins/cache/understand-anything/understand-anything/<VERSION>/, and copying your fresh build into that directory before restarting Claude Code.

When developing extensions for Understand-Anything—a Claude Code plugin—you need a rapid iteration workflow that doesn't require full reinstallation. Since Claude Code maintains a version-specific cache of installed plugins, you must manually replace these cached files with your locally built versions to see changes immediately.

Understanding Claude Code's Plugin Cache System

Claude Code stores plugin files in a user-specific cache directory that follows a strict versioning scheme. The system does not follow symbolic links, which means you cannot use ln -s shortcuts for development workflows.

The cache location follows this pattern:

~/.claude/plugins/cache/understand-anything/understand-anything/<VERSION>/

The <VERSION> string corresponds exactly to the version field in understand-anything-plugin/package.json. Claude Code loads plugin code exclusively from this cached location during runtime, making it the only viable injection point for local modifications.

Step-by-Step Workflow for Testing Local Changes

Build the Modified Packages

Before copying files to the cache, compile your TypeScript changes. Run the PNPM build commands for both the core library and any skill packages you modified:

# Build the core package

pnpm --filter @understand-anything/core build

# Build skill packages

pnpm --filter @understand-anything/skill build

These commands generate the compiled JavaScript and asset files in your local understand-anything-plugin directory.

Identify the Cached Version

Inspect the existing cache to determine which version Claude Code currently expects:

ls ~/.claude/plugins/cache/understand-anything/understand-anything/

This outputs a version folder name (for example, 2.5.1) that matches the version declared in your package.json. You must use this exact string in the next steps.

Clear the Old Cache

Delete the entire version-specific folder to prevent stale files from interfering with your new build:

rm -rf ~/.claude/plugins/cache/understand-anything/understand-anything/2.5.1

Removing the directory ensures that no outdated compiled assets or deleted files persist in the cache.

Copy the Fresh Build

Copy your locally built understand-anything-plugin directory into the cache location, replacing the placeholder with the version you identified:

cp -R ./understand-anything-plugin \
  ~/.claude/plugins/cache/understand-anything/understand-anything/2.5.1

This command places your development build exactly where Claude Code expects to find the production plugin code.

Restart Claude Code

Close all active Claude Code sessions and open a new one. The fresh session loads the updated cache, while older sessions continue running the previous version they loaded into memory.

Key Files and Validation

When testing local changes, pay attention to these critical files:

• understand-anything-plugin/package.json – Contains the version string that determines the cache folder name. Claude Code uses this value to locate the plugin code.
• understand-anything-plugin/skills/**/SKILL.md – Markdown skill definitions that Claude Code reads to execute domain-specific tasks. Changes here affect the plugin's capabilities.
• understand-anything-plugin/agents/**.md – Agent orchestration scripts that control analysis workflows. Modifications change how the plugin processes inputs.
• CLAUDE.md – The official documentation file containing the Testing Local Plugin Changes section that validates this workflow.

Summary

• Claude Code caches plugins at ~/.claude/plugins/cache/understand-anything/understand-anything/<VERSION>/ and ignores symlinks.
• Build locally first using pnpm --filter commands for the core and skill packages.
• Match the version string exactly by checking the existing cache directory name.
• Delete before copying to ensure no stale files remain in the cache.
• Restart sessions to load the updated plugin code; existing sessions retain the old version.

Frequently Asked Questions

Why can't I use symlinks for local plugin development?

Claude Code does not follow symlinks when loading plugin files, according to the Understand-Anything source documentation in CLAUDE.md. This security and reliability measure prevents broken references and ensures consistent file system behavior across different operating systems. You must perform physical copies with cp -R instead.

Do I need to bump the version number for every change?

No. You only need to modify the version in understand-anything-plugin/package.json if you want to maintain multiple plugin versions side-by-side. For rapid iteration, you can overwrite the existing version folder repeatedly without changing the version string, as long as you clear the old cache first.

Where does Claude Code store the plugin cache?

The cache resides in the user's home directory at ~/.claude/plugins/cache/understand-anything/understand-anything/<VERSION>/. This location is consistent across Claude Code installations and is version-specific, meaning each installed version maintains its own isolated directory.

How do I know which version Claude Code is currently using?

List the contents of the cache parent directory with ls ~/.claude/plugins/cache/understand-anything/understand-anything/. The folder name you see (such as 2.5.1) corresponds to the version field in understand-anything-plugin/package.json. This folder must exist and match the version declared in the plugin manifest for Claude Code to load the code successfully.

{
  "mcpServers": {
    "instagit": {
      "command": "npx",
      "args": ["-y", "instagit@latest"]
    }
  }
}