# <Concept Title>

Source:
- <primary source url>
- <secondary source url>

Status: draft|adopted|deprecated
Decision level: advisory|mandatory
Applies to: api-runtime|workers|tests
Last reviewed: YYYY-MM-DD

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## Purpose

Describe what this concept governs and why it exists.

## Scope and Non-Goals

- In scope:
- Out of scope:

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## Rules

- Rule 1
- Rule 2

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## Recommended Pattern

```python
# minimal example
```

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## Anti-Patterns

- Anti-pattern 1
- Anti-pattern 2

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## Operational Checks

- Check 1
- Check 2

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## Testing Checks

- Test 1
- Test 2

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## Migration Notes

- Staged rollout notes and compatibility caveats.