Schema Reference - Model Context Protocol

Created 1/28/2026 at 12:29:59 AM

interface ToolAnnotations { title?: string; readOnlyHint?: boolean; destructiveHint?: boolean; idempotentHint?: boolean; openWorldHint?: boolean; }

Additional properties describing a Tool to clients.

NOTE: all properties in ToolAnnotations are hints. They are not guaranteed to provide a faithful description of tool behavior (including descriptive properties like title).

Clients should never make tool use decisions based on ToolAnnotations received from untrusted servers.

Public