Bedrock AgentCore Runtime adds session endpoints: preview a web app in your own browser while a coding agent edits it in the cloud
What cloud agents lacked was a way to see the result; this gives each session an authenticated preview URL that expires with it.
// Key points
- Each session gets an authenticated URL that forwards HTTP and WebSocket requests to allowed ports; allowedPorts takes 1 to 5 entries within 8000 to 12000.
- It supports HTTP/1.1, HTTP/2, server-sent events, gRPC and WebSocket; URLs are scoped to one session and stop working when it ends.
- IAM runtimes require SigV4 signing and the bedrock-agentcore:InvokeAgentRuntimeProxy permission; since browsers cannot sign requests, the SDK opens a local endpoint that adds credentials and forwards them.
- Limits: microVM runtimes only, public HTTPS only, and no AWS PrivateLink for inbound connections.
Builder's takeIf you run your own agent platform, copy the design as is: preview URLs issued per session, expiring with it and limited to allowlisted ports are far safer than opening public ports on a sandbox. It fits content-generation backends like PandaClaws too, letting people see the page an agent produced before it ships instead of reading logs; note there is no PrivateLink, so hold off for internal-only projects.
// Background · from #AI agents
Full timeline →- Nov 1 AWS lays out an end-to-end Bedrock cost playbook: spend attributed to each IAM principal, over-budget users blocked in seconds to minutes, and more than half of coding-fleet calls on cheaper models
- Nov 1 Microsoft Research evaluates Copilot on synthetic enterprises: three industry environments with hundreds of users each, saving about $100,000 per evaluation dataset
- Oct 31 Gemini API's Computer Use tool is generally available across the Interactions and GenerateContent APIs, with Gemini 3.8 Flash as the recommended model