Writing Plugins

Overview

Plugins extend OpenCode by hooking into events and customizing behavior. They're JavaScript/TypeScript modules that export functions receiving a context object and returning hooks.

When to Use

• Creating event-driven automation (notifications, logging, protection)
• Adding custom tools to OpenCode
• Modifying tool behavior before/after execution
• Customizing session compaction behavior
• Integrating with external services

Don't use for: simple prompts (use commands), static configuration (use config), or agent behavior (use agents).

File Locations