API Design interview questions

Design clean, evolvable APIs: resource modeling, versioning, pagination, error semantics, and contracts that survive change.

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Real API Design questions reported from interviews at 50+ AI companies, with the golden answer and full production scoring. Unlock with Pro →

Resilient LLM API calls with exponential backoff retry logicReported at Anthropiceasy
LLM retry logic causes infinite loops on malformed API responsesReported at Metaeasy
Sliding Window Rate Limiter for Concurrent LLM API CallsReported at Databricksmedium
AI Agent Loop Termination Bug Causes Excessive API CallsReported at Googlemedium
TDD — Tests First for a Retry Policy with IdempotencyReported at Stripehard

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