Context surface

A context_surface describes what context was available before a selection decision. It is the context equivalent of a tool surface: small enough to reason about, large enough to explain omissions.

Fields

A surface SHOULD include surface_id, scope, producer, available_source_refs, available_item_refs, capability_refs, policy_refs, visibility, created_at, expires_at, and metadata.

Surface kinds

• turn_surface
• task_surface
• session_surface
• tool_surface
• review_surface
• handoff_surface
• custom

Fixed rule

Do not expose the whole world as a surface. Large catalogs should be represented through discovery, search, retrieval, or deferred source refs.