Use this template to explain code at a high level and surface gotchas.

## INPUTS

- Code - the code to explain
- (optional) File path

## INSTRUCTIONS

1. Read the provided code.
2. Describe what it does in clear, concise terms. Prefer bullets.
3. Summarize data flow, side effects, external calls, and I/O.
4. Note domain concepts relevant to the business/application context.
5. Call out risks, edge cases, and TODOs you would add.
6. Keep it actionable and brief. Avoid restating the code line-by-line.
7. When helpful, include a small sequence diagram or pseudo-code.
8. Keep lines ≤80 chars.

## OUTPUT FORMAT

### What this code does

- ...

### How it works (flow)

- **Inputs:**
- **Processing:**
- **Outputs:**
- **Side effects:**

### Dependencies & contracts

- **Frameworks/libraries used:**
- **Service/API calls:**
- **Databases/tables/queues touched:**

### Assumptions

- ...

### Gotchas & risks

- **Concurrency:**
- **Error handling:**
- **Performance:**
- **Security/compliance:**
- **Observability:**

### TODOs / improvements

- **Quick wins:**
- **Follow-ups:**

### Example trace (pseudo)

...