A "sent" prompt could vanish with no trace on a flaky connection (e.g. a train):
with local echo on, Enter cleared the overlay then sent over the WebSocket
fire-and-forget. On a half-open socket (readyState===OPEN, dead TCP) ws.send()
doesn't throw, so the frame was silently discarded, nothing was enqueued, and
navigator.onLine stayed true — the prompt was lost and never resent.
Replace the best-effort offline queue with a durable, acknowledged delivery layer:
- Client (app.js): every input frame is recorded with a stable clientId +
monotonic per-session seq and persisted to localStorage BEFORE delivery, and
only dropped on a server ACK. Delivered over WS (acked via {t:'ia',seq}) or,
when the socket is down, POST in seq order (HTTP 2xx = ACK). A 2s sweep
force-reconnects a WS whose oldest frame is unacked past 4s (half-open sockets
never recover on their own); on reconnect/reload all pending frames re-deliver.
Survives reconnects AND page reloads. Connection indicator shows pending count.
- Server: Session.shouldApplyInput(clientId, seq) applies each frame exactly once
(bounded MRU map); ws-routes + POST /input dedup a redelivered seq but still ACK
it (200 / {t:'ia'}), so an at-least-once resend can never type the prompt twice.
Untagged input (curl/legacy) applies unconditionally — no behavior change.
- terminal-ui.js sendInput() (voice / keyboard-accessory / paste) now routes
through the same durable layer.
Tests: test/reliable-input-dedup.test.ts (exactly-once semantics on the real
Session) + POST /input dedup route tests. Design: docs/reliable-input-delivery.md.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Codeman maintainer
1255e28f6f