Running an agent without a version selector will follow its live alias

Agents already have immutable versions and named release aliases, and live already resolves when you ask for it explicitly. We are now changing what happens when you ask for nothing.

What changes. Running an agent with no version selector will resolve its live alias and run that exact version, instead of the agent's current editable configuration. Concretely:

• Saving an agent will no longer change what runs. A save creates a candidate version; live keeps serving until you deploy. The agent page tells you when unpublished edits exist.
• Deploy to live and Rollback move the pointer and record a deployment receipt. Nothing else about the agent changes.
• Before we turn the change on for an organization, we point every one of its agents at the configuration it is running today, so nothing changes behavior on the day itself. An agent whose current configuration has been edited since it was last deployed is the one exception: after the change it runs its deployed version, so deploy those edits first if you want them live.
• Agents created from the dashboard, from a template, or as part of a product are deployed to live as they are created. An agent created by runtype ensure without publishing stays undeployed on purpose; its first run deploys its current configuration as version 1.

What does not change. Explicit selectors (agent.alias, agent.versionId) behave as they do today: they already resolve the version they name. Preview aliases stay preview aliases. Agents that run outside Runtype (external) and Claude Managed agents keep their current behavior.

Rollout. The change is off for everyone today. We are turning it on one organization at a time, watching for anything that stops resolving, and we can turn it back off for an organization instantly without a deploy. If an agent has archived its live alias when the change reaches you, running it answers AGENT_NOT_DEPLOYED with the fix in the message, rather than silently running a draft.