Known issues

Plan for current API limits and their workarounds.

At a glance

Checked
4 September 2026
Scope
Builder-facing API
Runtime
Current deployment
Status
Open

Open issues

IssueImpactWorkaround
Run admission latencyA run takes about 2.7 seconds to create.Show a pending state and open the stream immediately.
Sandbox session latencyA sandbox-backed session takes about 2.5 seconds to create.Create sessions before the user needs them when appropriate.
Coarse live-bus resyncOne publisher failure can resync every subscriber on a session.Handle stream.resync and replay durable events.
Strict tool output schemaOne shared schema can reject valid operation-specific results.Use oneOf or omit fields that do not apply.
MCP servers are not dispatched, 4 September 2026Agents accept MCP server configuration, but the runtime does not dispatch it.Use application tools.
OpenAPI prose gapsSome new fields and routes have limited contract examples.Use these guides with api/openapi/openapi.yaml and the smoke flow.
Claim fairnessA stuck older run can delay another tenant.Use client timeouts and retry only safe requests.
Compensation claim raceTwo workers can race expired-sandbox cleanup.Treat cleanup errors as transient and inspect final session state.
Admission finalization raceA stale worker can race failure finalization.Use terminal events as the final client state.

Recently fixed

  • Slug sessions prefer the active deployment, or the newest published deployment when none is active.
  • Tool lifecycle events now share one tool_call_id.
  • New sessions can use refreshed legacy deployment snapshots.
  • Streams now deliver live deltas and structured content.
  • Waiting application tools now have a 30 minute default deadline.

Pitfalls

  • This page is date-bound: Check the Changelog before assuming an item is still open.
  • Todo UI issues are separate: Do not infer an API failure from a tenant rendering defect.