Runtime changelog, 30 October 2026

What shipped in Runtime Cloud on 30 October 2026: usage export shows the carry on each outbound traffic row; the MCP server accepts newer protocol versions; and a sandbox's lease counts from when it first runs.

Usage export shows the carry on each outbound traffic row

In GET /v1/usage/export, each sandbox egress row's outbound measurements now include carried: the fraction of a microdollar the row started from, carried in from earlier outbound traffic in the same month, in bytes times microdollars per decimal GB. The row's charge plus written_off_micros equals floor((carried + billable bytes × rate) / 1,000,000,000). Charges are unchanged.

The MCP server accepts newer protocol versions

A client that requests an MCP protocol version newer than the server supports, such as 2026-07-28, now gets a working session at the server's newest version (2025-11-25). This applies to initialize and to the MCP-Protocol-Version header on later requests. Before, those later requests returned 400 Bad Request: Unsupported protocol version, so clients such as Claude's connectors could not connect. A malformed version, or one older than the server supports, still returns 400.

A sandbox's lease counts from when it first runs

A paid sandbox that waits in starting for its server to have room now has its lease renewed while it waits, so it is no longer stopped with time_limit before it ever runs, and its server no longer refuses the start as invalid_lease once the wait used up its lease. No compute is charged for the time spent waiting. diskKept on a stopped sandbox is now true only when POST /v1/sandboxes/{id}:restart starts it from its disk: a stopped sandbox whose server was lost now returns diskKept: false.