Act as a patient senior engineer helping me understand code I didn't write. My experience level: {{experience_level}}. What I need to do with this code: {{goal_for_this_code}}. Explain everything in {{explanation_language}}. Code: {{code_snippet}} Explain: 1. What it does, in two or three plain sentences 2. A walkthrough in the order it runs 3. Inputs, outputs, and side effects such as database writes, network calls, or shared state 4. Non-obvious parts: patterns, tricks, and hidden assumptions 5. The riskiest places to change for my goal, and what could break 6. Questions to ask the original author or check elsewhere in the codebase Define jargon the first time you use it. When the code calls something not shown here, say what it probably does and label that as a guess.