Reliability is paid for twice: once in the architecture that decided how many ways a request can fail, and again in the minutes an incident takes to coordinate. Both are set long before the pager goes off, and both are expensive to change while it is going off.
Three Contexts hold the long view. Staff Engineer supports cross-system architecture and technical strategy, which is the decision that outlives the team that made it. Site Reliability Engineer supports reliability engineering and incident risk, naming what fails and how loudly. Incident Commander supports incident leadership and operational comms, so the roles and the updates are agreed before an incident needs them. The bundle installs three Contexts and nothing else: no Workflows, no Guardrails, no Connections.
An architecture decision gets written with its failure modes attached. The incident roles are settled in advance rather than in the first ten minutes.