agui-event-contract

Standardize AG-UI SSE streaming events by enforcing a strict event contract that defines required fields, deterministic event ordering, and naming conventions across the run lifecycle, text streaming, tool calls, and state updates. This prevents contract drift and ensures reliable frontend aggregation.

Multi-agent SSE event aggregation requires standardizing message attribution via stable identifiers like runId, messageId, and toolCallId. This ensures correct grouping and rendering of interleaved STATE_UPDATE messaging and ordered_parallel strategies across concurrent agent streams.

Sticky packets and partial chunks break frontend parsing when SSE wire format rules are not enforced. Establishing robust SSE framing requirements and strict JSON parsing protocols prevents malformed payloads, split chunks, and flush termination mistakes during streaming.

Safe error handling in AG-UI event streams requires enforcing stable error codes and strict sensitive data redaction. This prevents leaking internal information while maintaining deterministic error messaging for the frontend during run lifecycle failures.

Yes, the AG-UI event contract supports multi-agent ordered_parallel strategies and interleaved STATE_UPDATE messaging. It enforces deterministic event ordering and strict delta/content compatibility to ensure the frontend can aggregate state updates without broken sequencing.

You need a strict event contract for AgentHub SSE streaming when building single-agent or multi-agent interfaces that require reliable frontend rendering. It is necessary to prevent malformed payloads, enforce field typing conventions, and guarantee deterministic event ordering.