Question 1

AI observability: how do you trace and log LLM calls in prod?

Accepted Answer

**Target Audience:** Developers who have an LLM feature or agent in production and want to see each model call, tool call and its timing; no prior observability experience assumed.
**Difficulty:** Easy
**Verified with:** Node 22.22.0 and Python 3.12.3 (the in-process tracer below, identical output in both). OpenTelemetry convention names, the W3C header format and SDK options were checked with web searches in October 2026; where only secondary sources were found, the text says so.

> **How to re

Question 2

What should you log and trace in an LLM application?

Accepted Answer

**Target Audience:** Engineers building their first production LLM feature who need to decide what goes into logs, metrics and traces; also interview candidates who will be asked "how would you debug a bad answer?".
**Difficulty:** Medium
**Verified with:** Node 22.22.0 and Python 3.12.3 (the log-record builder below, identical output in both). Prices in the example are made-up round numbers, not any provider's price list.

> **How to read this doc:** Every idea is explained in plain language fi

Question 3

How should an agent handle tool errors, timeouts and retries?

Accepted Answer

**Target Audience:** Engineers putting an agent in front of real APIs, where things fail every day, and anyone asked to explain how an agent stays reliable when its tools do not.
**Difficulty:** Hard
**Verified with:** Node 22.22.0 and Python 3.12.3 (both examples below, identical output). Error-result formats were checked in October 2026 against the Anthropic "Handle tool calls" docs page and the MCP tools specification (modelcontextprotocol.io).

> **How to read this doc:** Every idea is expla

Question 4

Guardrails for AI agents: rate limits, budget caps, and HITL?

Accepted Answer

**Target Audience:** Engineers running agents in production who need them to stop safely, and candidates asked "what stops your agent from looping forever or spending a fortune?"
**Difficulty:** Hard
**Verified with:** Node 22.22.0 and Python 3.12.3 (both examples, identical output). Framework limits were checked in October 2026: AI SDK `ai` 7.0.143 type definitions (read from the published package) and the OpenAI Agents SDK reference docs (via web search). Prices in the examples are stated assu

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Easy

AI observability: how do you trace and log LLM calls in prod?

Medium

What should you log and trace in an LLM application?

Hard

How should an agent handle tool errors, timeouts and retries?

Guardrails for AI agents: rate limits, budget caps, and HITL?