extension.wit

package pi:extension;

/// Host-provided connector surface (capability-gated by Pi).
///
/// This is intentionally narrow. Extensions should call into Pi using a small
/// set of connector operations rather than Node/Bun OS APIs.
interface host {
  /// Generic connector call. Input/output are JSON strings.
  call: func(name: string, input-json: string) -> result<string, string>;
}

interface extension {
  /// Initialize the extension and return its registration payload (JSON).
  init: func(manifest-json: string) -> result<string, string>;

  /// Handle a tool call. Returns tool_result JSON.
  handle-tool: func(name: string, input-json: string) -> result<string, string>;

  /// Handle a slash command. Returns slash_result JSON.
  handle-slash: func(command: string, args: list<string>, input-json: string) -> result<string, string>;

  /// Handle an event hook. Returns optional event response JSON.
  handle-event: func(event-json: string) -> result<string, string>;

  /// Clean shutdown (optional).
  shutdown: func();
}

world pi-extension {
  import host;
  export extension;
}