Realtime agent↔user channel

Scores as of 2026-09-14 (43 days old; Depot marks scores stale after 30 days). The pick is still Depot's current editorial pick; it has not been re-reviewed since. Prices below carry their own dates.

Depot Pick

Ably · 8.29/10 for this job (curated estimate, high confidence)

Reliability + dx for realtime fanout. Distinct from notification-orchestration and serverless-agent-queue.

Runner-up

Stream (GetStream) · 7.94/10

Scores higher than the pick on: Developer & agent DX.

When not to use the pick

Need full chat UX (channels, moderation, reactions) — Stream; only server-side job fanout — QStash/SQS/EventBridge; Cloudflare Durable Objects already hold your edge state.

Lock-in / migration

The pick has lower stored lock-in risk than runner-up Stream (GetStream) (5.2 vs 5.5). Self-host fallback listed for this job: Centrifugo.

Sourced price (no comparable unit)

Pick: no sourced price in this job's unit (no_matching_sourced_price).

No cheapest SKU (no_comparable_unit_for_job). No price was invented.

Free option

• Centrifugo (oss) — source, as of 2026-10-25

Failure modes to watch

• Confirmation skip: Gate those tool names on an approval id recorded before the call. A missing approval is a failure even if the downstream tool returns success.
• Context overflow: If the input exceeds the window, say so and retrieve a narrower slice. Do not answer from a truncated head as if it were the whole source.
• Identity confusion: Bind every tool call to a user or tenant id. Refuse the call if that id changed mid-task. For a public bot, the operator owns the words the bot shows.
• Instruction drift: Restate the stop condition in the trace. End the run when it is met. Review long traces for steps that do not serve the original task.
• Prompt injection: Compare each tool call to the original user task. If the call only makes sense given text that arrived from a fetched page, file, or message, stop and ask. Record which source the instruction came from. This catalog does not store payloads or attack steps.
• Stale retrieval: Store the source URL and the time it was fetched. If a newer canonical page exists, or two stored sources disagree, do not answer from the older one.

Reported outcomes (submitted reports only)

This job: loading… JSON · reports never change scores · seed/test records excluded

Depot Pick (Ably) on this job: loading… JSON · reports never change scores · seed/test records excluded

Cite: Agent Provider Depot, Depot Pick for realtime-agent-channel: ably, scores as of 2026-09-14. Agents: GET /api/decide?jtbd=realtime-agent-channel