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Plugins in the SDK

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Documentation Index

Fetch the complete documentation index at: https://code.claude.com/docs/llms.txt Use this file to discover all available pages before exploring further.

Plugins in the SDK

Load custom plugins to extend Claude Code with commands, agents, skills, and hooks through the Agent SDK

Plugins allow you to extend Claude Code with custom functionality that can be shared across projects. Through the Agent SDK, you can programmatically load plugins from local directories to add custom slash commands, agents, skills, hooks, and MCP servers to your agent sessions.

What are plugins?

Plugins are packages of Claude Code extensions that can include:

The commands/ directory is a legacy format. Use skills/ for new plugins. Claude Code continues to support both formats for backward compatibility.

For complete information on plugin structure and how to create plugins, see Plugins.

Loading plugins

Load plugins by providing their local file system paths in your options configuration. The SDK supports loading multiple plugins from different locations.

```typescript TypeScript theme={null} import { query } from "@anthropic-ai/claude-agent-sdk";

for await (const message of query({ prompt: "Hello", options: { plugins: [ { type: "local", path: "./my-plugin" }, { type: "local", path: "/absolute/path/to/another-plugin" } ] } })) { // Plugin commands, agents, and other features are now available } ```

```python Python theme={null} import asyncio from claude_agent_sdk import query

async def main(): async for message in query( prompt="Hello", options={ "plugins": [ {"type": "local", "path": "./my-plugin"}, {"type": "local", "path": "/absolute/path/to/another-plugin"}, ] }, ): # Plugin commands, agents, and other features are now available pass

asyncio.run(main()) ```

Path specifications

Plugin paths can be:

The path should point to the plugin's root directory (the directory containing .claude-plugin/plugin.json).

Verifying plugin installation

When plugins load successfully, they appear in the system initialization message. You can verify that your plugins are available:

```typescript TypeScript theme={null} import { query } from "@anthropic-ai/claude-agent-sdk";

for await (const message of query({ prompt: "Hello", options: { plugins: [{ type: "local", path: "./my-plugin" }] } })) { if (message.type === "system" && message.subtype === "init") { // Check loaded plugins console.log("Plugins:", message.plugins); // Example: [{ name: "my-plugin", path: "./my-plugin" }]

  // Check available commands from plugins
  console.log("Commands:", message.slash_commands);
  // Example: ["/help", "/compact", "my-plugin:custom-command"]
}

} ```

```python Python theme={null} import asyncio from claude_agent_sdk import query

async def main(): async for message in query( prompt="Hello", options={"plugins": [{"type": "local", "path": "./my-plugin"}]} ): if message.type == "system" and message.subtype == "init": # Check loaded plugins print("Plugins:", message.data.get("plugins")) # Example: [{"name": "my-plugin", "path": "./my-plugin"}]

          # Check available commands from plugins
          print("Commands:", message.data.get("slash_commands"))
          # Example: ["/help", "/compact", "my-plugin:custom-command"]

asyncio.run(main()) ```

Using plugin skills

Skills from plugins are automatically namespaced with the plugin name to avoid conflicts. When invoked as slash commands, the format is plugin-name:skill-name.

```typescript TypeScript theme={null} import { query } from "@anthropic-ai/claude-agent-sdk";

// Load a plugin with a custom /greet skill for await (const message of query({ prompt: "/my-plugin:greet", // Use plugin skill with namespace options: { plugins: [{ type: "local", path: "./my-plugin" }] } })) { // Claude executes the custom greeting skill from the plugin if (message.type === "assistant") { console.log(message.message.content); } } ```

```python Python theme={null} import asyncio from claude_agent_sdk import query, AssistantMessage, TextBlock

async def main(): # Load a plugin with a custom /greet skill async for message in query( prompt="/demo-plugin:greet", # Use plugin skill with namespace options={"plugins": [{"type": "local", "path": "./plugins/demo-plugin"}]}, ): # Claude executes the custom greeting skill from the plugin if isinstance(message, AssistantMessage): for block in message.content: if isinstance(block, TextBlock): print(f"Claude: {block.text}")

asyncio.run(main()) ```

If you installed a plugin via the CLI (for example, /plugin install my-plugin@marketplace), you can still use it in the SDK by providing its installation path. Check ~/.claude/plugins/ for CLI-installed plugins.

Complete example

Here's a full example demonstrating plugin loading and usage:

```typescript TypeScript theme={null} import { query } from "@anthropic-ai/claude-agent-sdk"; import * as path from "path";

async function runWithPlugin() { const pluginPath = path.join(__dirname, "plugins", "my-plugin");

console.log("Loading plugin from:", pluginPath);

for await (const message of query({
  prompt: "What custom commands do you have available?",
  options: {
    plugins: [{ type: "local", path: pluginPath }],
    maxTurns: 3
  }
})) {
  if (message.type === "system" && message.subtype === "init") {
    console.log("Loaded plugins:", message.plugins);
    console.log("Available commands:", message.slash_commands);
  }

  if (message.type === "assistant") {
    console.log("Assistant:", message.message.content);
  }
}

}

runWithPlugin().catch(console.error); ```

```python Python theme={null} #!/usr/bin/env python3 """Example demonstrating how to use plugins with the Agent SDK."""

from pathlib import Path import anyio from claude_agent_sdk import ( AssistantMessage, ClaudeAgentOptions, TextBlock, query, )

async def run_with_plugin(): """Example using a custom plugin.""" plugin_path = Path(file).parent / "plugins" / "demo-plugin"

  print(f"Loading plugin from: {plugin_path}")

  options = ClaudeAgentOptions(
      plugins=[{"type": "local", "path": str(plugin_path)}],
      max_turns=3,
  )

  async for message in query(
      prompt="What custom commands do you have available?", options=options
  ):
      if message.type == "system" and message.subtype == "init":
          print(f"Loaded plugins: {message.data.get('plugins')}")
          print(f"Available commands: {message.data.get('slash_commands')}")

      if isinstance(message, AssistantMessage):
          for block in message.content:
              if isinstance(block, TextBlock):
                  print(f"Assistant: {block.text}")

if name == "main": anyio.run(run_with_plugin) ```

Plugin structure reference

A plugin directory must contain a .claude-plugin/plugin.json manifest file. It can optionally include:

```text theme={null} my-plugin/ ├── .claude-plugin/ │ └── plugin.json # Required: plugin manifest ├── skills/ # Agent Skills (invoked autonomously or via /skill-name) │ └── my-skill/ │ └── SKILL.md ├── commands/ # Legacy: use skills/ instead │ └── custom-cmd.md ├── agents/ # Custom agents │ └── specialist.md ├── hooks/ # Event handlers │ └── hooks.json └── .mcp.json # MCP server definitions


For detailed information on creating plugins, see:

* [Plugins](https://code.claude.com/en/plugins) - Complete plugin development guide
* [Plugins reference](https://code.claude.com/en/plugins-reference) - Technical specifications and schemas

## Common use cases

### Development and testing

Load plugins during development without installing them globally:

```typescript theme={null}
plugins: [{ type: "local", path: "./dev-plugins/my-plugin" }];

Project-specific extensions

Include plugins in your project repository for team-wide consistency:

```typescript theme={null} plugins: [{ type: "local", path: "./project-plugins/team-workflows" }];


### Multiple plugin sources

Combine plugins from different locations:

```typescript theme={null}
plugins: [
  { type: "local", path: "./local-plugin" },
  { type: "local", path: "~/.claude/custom-plugins/shared-plugin" }
];

Troubleshooting

Plugin not loading

If your plugin doesn't appear in the init message:

  1. Check the path: Ensure the path points to the plugin root directory (containing .claude-plugin/)
  2. Validate plugin.json: Ensure your manifest file has valid JSON syntax
  3. Check file permissions: Ensure the plugin directory is readable

Skills not appearing

If plugin skills don't work:

  1. Use the namespace: Plugin skills require the plugin-name:skill-name format when invoked as slash commands
  2. Check init message: Verify the skill appears in slash_commands with the correct namespace
  3. Validate skill files: Ensure each skill has a SKILL.md file in its own subdirectory under skills/ (for example, skills/my-skill/SKILL.md)

Path resolution issues

If relative paths don't work:

  1. Check working directory: Relative paths are resolved from your current working directory
  2. Use absolute paths: For reliability, consider using absolute paths
  3. Normalize paths: Use path utilities to construct paths correctly

See also