How would you reduce AI inference cost sustainably?
### Signal to interviewer
I can reduce inference costs while preserving outcomes by tying optimization to value and quality signals.
### Clarify
I would clarify cost pressure horizon, margin goals, quality floors, and which workloads are economically misaligned.
### Approach
Run a unit-economics optimization loop: measure cost-to-value, prioritize high-burn low-value flows, and deploy routing/caching/prompt controls iteratively.
### Metrics & instrumentation
Primary metric: cost per successful task completion. Secondary metrics: route efficiency, cache hit value, and token waste ratio. Guardrails: task success decline, user churn, and increased support handoffs.
### Tradeoffs
Cheaper routing lowers spend but can underperform on hard tasks. Premium routing raises quality but may break margin discipline.
### Risks & mitigations
Risk: hidden quality decay from cost cuts; mitigate with paired quality monitors. Risk: optimization debt accumulation; mitigate with monthly burn-down reviews. Risk: user behavior shifts increase spend; mitigate with UX nudges and defaults.
### Example
A support copilot routes simple account queries to lightweight models and escalates only unresolved cases to higher-cost reasoning routes.
### 90-second version
Optimize inference cost as a continuous loop anchored on cost per successful outcome. Apply routing and efficiency levers while protecting quality and retention guardrails.
- Which workflows currently have the worst cost-to-value ratio?
- What quality floor is non-negotiable during cost optimization?
- How would you design adaptive routing policies by request complexity?
- What governance cadence keeps cost and quality balanced over time?