Expand description
The small event protocol shared by agent frontends.
Structs§
- Approval
Call - Assistant
Content Delta Event - Assistant
Message Event - Error
Event - Event
- An event emitted to a frontend.
- Exec
Approval Request Event - Frontend
Action - One labeled, icon-forward action attached to a list item.
- Frontend
Action List Item - One compact status row with optional trailing actions.
- Frontend
Block - Capability-rendered transcript content with frontend-neutral formatting and tone.
- Frontend
Command - A frontend command declared by a capability.
- Frontend
Contribution - UI metadata exported by one capability.
- Frontend
Picker Option - One selectable action supplied by a capability.
- Frontend
Preview Event - One timestamped semantic event shown inside a capability preview.
- Frontend
Progress - Determinate progress rendered by a frontend widget.
- Frontend
Reference - One chat reference supplied by a capability.
- Frontend
Setting - One schema-advertised setting rendered by a thin frontend.
- Frontend
Setting Option - One exact value in a schema-advertised select control.
- Frontend
Widget - One capability-rendered view mounted into a standard frontend slot.
- Message
Event - One accepted conversation message.
- Message
Submission - One provider-neutral conversation message submitted to an agent.
- Message
Target - Exact durable transcript prefix selected by a message action.
- Middleware
Feature - One middleware entry and its frontend-neutral configuration controls.
- Model
Changed Event - Model
Choice - One selectable runtime model route.
- Model
Info - Human-readable model settings exposed to frontends.
- Model
Step Completed Event - The terminal record for one provider request.
- Model
Step Content - One complete normalized text item produced by a model step.
- Model
Step Diagnostics - Provider-owned cost and prompt-cache observations for one completed request.
- Model
Step Started Event - One provider request becoming active within a turn.
- Prompt
Cache Diagnostics - Prompt-cache behavior observed for one completed request.
- Rendered
Block - A block together with its explicit semantic owner.
- Session
Configured Event - Immutable session data emitted once when an agent starts or resumes.
- Session
Context - Frontend-visible context for the session owner, workspace, and origin.
- Session
File Limits - Session-file policy advertised to frontends by the owning runtime.
- Session
File Record - One stored session file together with its producer.
- Session
File Reference - One immutable, session-bound file addressed by an opaque reference.
- Session
History Event - A restored transcript kept distinct from live turn lifecycle events.
- Session
Resume Requested Event - Submission
- A command submitted by a frontend.
- Submission
Rejected Event - A submission the agent rejected without changing durable turn state.
- Token
Count Event - Token
Usage - Token
Usage Info - Tool
Call Begin Event - Tool
Call EndEvent - Tool
Load Event - Deferred tool schemas materialized at one model-context position.
- Turn
Aborted Event - Turn
Complete Event - Turn
Started Event - Warning
Event - WebSearch
Begin Event - WebSearch
EndEvent
Enums§
- Active
Message Delivery - Requested delivery for a message submitted while a turn is active.
- Error
Kind - Stable frontend classification for framework failures.
- Event
Msg - Events supported by the minimal frontend contract.
- Frontend
Block Format - Frontend-neutral structure carried by a transcript block.
- Frontend
Block Role - Semantic category used for grouping, summaries, filtering, and icons.
- Frontend
Block State - Lifecycle state of one rendered transcript block.
- Frontend
Block Update - How a block changes the matching capability-scoped ID.
- Frontend
Event - Generic capability UI updates understood by every frontend.
- Frontend
List Item State - Semantic state for one compact list row.
- Frontend
Preview Update - How one preview page changes the matching frontend preview.
- Frontend
Setting Kind - Generic control metadata for a schema-advertised setting.
- Frontend
Setting Value - Scalar value accepted by the generic setting controls.
- Frontend
Slot - Stable locations a thin frontend shell makes available to capabilities.
- Frontend
Symbol - A presentation hint rather than a name from any one icon set, the same way
FrontendTonenames a role instead of a color. - Frontend
Tone - A presentation hint rather than a terminal-specific color.
- Frontend
Widget Content - Capability-owned content shown when a frontend widget is opened.
- Message
Author - Who submitted one conversation message.
- Message
Delivery - How one accepted message actually entered the conversation.
- Model
Event - Provider-neutral streaming output before submission correlation is attached.
- Model
Step Annotation - A provider-neutral annotation attached to one complete text part.
- Model
Step Content Phase - Semantic role of text preserved in a completed model step.
- Model
Step Outcome - Provider-neutral outcome of a completed model step.
- Op
- Commands supported by the agent.
- Prompt
Cache Mode - Provider-advertised prompt-cache behavior.
- Prompt
Cache Outcome - Cache result inferred from provider usage and local rewrite metadata.
- Review
Decision - A user’s decision for a paused tool batch.
- Session
File Origin - Which side of a session produced one stored file.
- Tool
Discovery Mode - How a model route makes newly discovered tool schemas available.
- WebSearch
Action - Provider-neutral action reported by hosted web search.
Constants§
- MAX_
CAPABILITY_ INPUT_ BYTES - Maximum UTF-8 bytes accepted in capability command input or a queued message edit.
- MAX_
MESSAGE_ BYTES - Maximum total UTF-8 bytes accepted in one user-input submission.
Functions§
- replay_
events - Reconstructs frontend-neutral events from positioned durable transcript items.