Summary

• Adds optional chat.send ACK server timing for operator UI clients so Control UI can separate server pre-ACK time from browser/request time on first sends.
• Preserves public WebChat behavior by omitting the new ACK timing payload for non-operator WebChat clients.
• Normalizes the optional timing payload in the Control UI controller and records the flattened values in existing control-ui.chat.send ACK timing events.
• Out of scope: changing send scheduling, model dispatch, transport auth, or visible chat rendering.

Linked context

Maintainer-requested follow-up for Control WebUI clean first-message slowness discovery.

Real behavior proof

• Behavior or issue addressed: Control UI first-send telemetry could not distinguish browser/network request duration from server-side pre-ACK work.
• Real environment tested: OpenClaw local linked worktree plus Blacksmith Testbox via Crabbox.
• Exact steps or command run after this patch:
  • node scripts/run-vitest.mjs run src/gateway/server.chat.gateway-server-chat-b.test.ts -- --reporter=verbose
  • node scripts/run-vitest.mjs run ui/src/ui/controllers/chat.test.ts ui/src/ui/app-chat.test.ts -- --reporter=verbose
  • node scripts/run-vitest.mjs run --config test/vitest/vitest.ui-e2e.config.ts --configLoader runner ui/src/ui/e2e/chat-flow.e2e.test.ts -- --reporter=verbose
  • git diff --check
  • OPENCLAW_OXLINT_SKIP_PREPARE=1 OPENCLAW_OXLINT_SKIP_LOCK=1 node scripts/run-oxlint.mjs --tsconfig config/tsconfig/oxlint.core.json src/gateway/server-methods/chat.ts src/gateway/server.chat.gateway-server-chat-b.test.ts ui/src/ui/controllers/chat.ts ui/src/ui/app-chat.ts ui/src/ui/controllers/chat.test.ts ui/src/ui/app-chat.test.ts
  • .agents/skills/autoreview/scripts/autoreview --mode branch --base origin/main
  • node scripts/crabbox-wrapper.mjs run --provider blacksmith-testbox --label control-first-message-next-rebased-check --idle-timeout 90m -- env OPENCLAW_CHECK_CHANGED_REMOTE_CHILD=1 OPENCLAW_CHANGED_LANES_RAW_SYNC=1 corepack pnpm check:changed
• Evidence after fix: Gateway test passes with Control UI mode=webchat receiving serverTiming; public webchat-ui regression verifies the field is omitted. Testbox tbx_01kt6jcjzh9esd723hvjnjvekh passed check:changed with lanes=core, coreTests.
• Observed result after fix: Control UI ACK timing events include serverReceivedToAckMs, serverLoadSessionMs, and optional serverPrepareAttachmentsMs when the Gateway provides them.
• What was not tested: live provider latency on a real user account.
• Proof limitations or environment constraints: mocked UI E2E validates the browser flow and gateway traffic shape; live provider runtime timing still needs field observation once merged.

Tests and validation

• Gateway focused: 31 tests passed.
• Control UI unit focused: 197 tests passed.
• Control UI mocked browser E2E: 12 tests passed.
• Static: git diff --check, targeted oxlint clean.
• Remote changed gate: Blacksmith Testbox through Crabbox passed on tbx_01kt6jcjzh9esd723hvjnjvekh.
• Autoreview: clean, no accepted/actionable findings.

Risk checklist

• Did user-visible behavior change? No
• Did config, environment, or migration behavior change? No
• Did security, auth, secrets, network, or tool execution behavior change? No
• Highest-risk area: accidentally exposing operator-only timing metadata to public WebChat clients.
• Mitigation: server gate uses operator UI identity, and regression coverage asserts public WebChat clients do not receive serverTiming.

Current review state

• Next action: wait for PR checks, then squash merge if clean.
• Waiting on: GitHub PR checks after push.
• Bot or reviewer comments addressed: local autoreview initially caught the Control UI mode=webchat gating bug; the fix and regression coverage are included.