Extending

Crystal Code is built to be changed in code. This section documents the extension points that exist today, the references a plugin or tool set may use, and the boundaries the host keeps.

Plugins

Plugins

One directory, one plugin.json, one assembly in its own load context.

Contract

Plugin contract

IPlugin, PluginContribution, attach phases, and the interfaces a plugin may implement.

Hooks

Hooks, raw hooks, and loading

Tool pipelines, privileged raw hooks, and load-context rules.

Tool sets

External tools

One directory, one tools.json, one runner, and the Plan and Work catalogs.

Exec

Exec tool sets

Stdin JSON, argv, content output, and the process contract.

.NET

Dotnet tool sets

Native text and multimodal tools loaded in an isolated context.

Prompts

Prompts and instructions

Prompt slots, prompt sets, attachments, and workspace instructions.

Skills

Skills

OpenCode-compatible instruction folders loaded on demand.