Key Takeaways:
1. Traditional observability optimizes storage around known queries; agentic observability has to survive the unknown ones, because the agent's job is to ask what no one anticipated.

2. Silent incompleteness is the real risk. An agent working from sampled, rolled-up, or aged-out data rarely errors out — it hands you a confident answer built on evidence that isn't there.

3. Retention, sampling, and rollups are decisions, not defaults. Each is a legitimate tool that also forecloses future questions. In an agentic world, those choices deserve to be made deliberately.