AI Transport

AI Transport is a drop-in durable session layer for AI applications, launched in 2023 by Ably and headquartered in London, UK. It is designed for developers building AI-powered chat, agentic workflows, and collaborative experiences who need conversations to survive disconnects, span multiple devices, and allow any client to signal any agent through the same session. The product runs on Ably's fault-tolerant global platform, which guarantees 99.999% uptime for enterprise plans and provides low-latency messaging across regions with elastic scale. AI Transport works with any AI model or framework, including OpenAI, Anthropic, Vercel AI SDK, LangChain, or custom stacks, and integrates via a few lines of code.

AI Transport replaces the fragile HTTP request-response pattern with a durable session that persists across network interruptions and device switches. Key capabilities include token streaming over sessions, cancellation of turns across devices (e.g., a stop button on a phone cancels a turn started on a laptop), reconnection and recovery without losing response state, multi-device sessions, history and replay of conversations, conversation branching, interruption management, concurrent turns handling, tool calling for integration, human-in-the-loop support, optimistic updates for UI, agent presence tracking, push notifications for session updates, chain of thought support, and double texting. The session layer allows any participant to publish, enabling real-time steering and collaboration.

In the realtime infrastructure market, AI Transport competes with PubNub, Pusher, Socket.IO, SignalR, Firebase, AWS IoT, Velt, and SAP NetWeaver. Unlike general-purpose pub/sub services like PubNub or Pusher, AI Transport is purpose-built for AI sessions, offering features like durable sessions, conversation branching, and chain of thought streaming that generic realtime platforms lack. However, it does not provide native voice or video support, and its React Chat UI Kit is less extensive than competitors like Stream or Sendbird. Moderation still requires third-party services, and the pricing model can be complex for large-scale deployments.

Honest trade-offs include the absence of native voice or video capabilities, which may require additional integrations for multimodal apps. The UI kit is limited compared to dedicated chat SDKs, and moderation relies on external providers. Pricing, while granular, can become opaque at high volumes due to separate charges for messages, channels, and connections. For teams needing a robust, globally distributed session layer for AI, AI Transport delivers, but it is not a full-stack chat platform or a replacement for specialized video or voice APIs.

Pay per minute or per MAU with granular control. Billed monthly on top of your package: Messages $2.50 per million, Channels $1.00 per million mins, Connections $1.00 per million mins. Enterprise plans offer 24/7 support, 99.999% uptime SLA, and committed use discounts.