# Regression Suite Design
> [!summary]
> Regression suites protect Lucia from losing behavior that already works.
---
## What a regression suite is
A regression suite is a saved custom prompt suite used repeatedly after changes.
It asks:
```text
Did this behavior stay fixed?
```
---
## What belongs in a regression suite
Include prompts that represent:
- previous bugs
- high-risk behaviors
- signature Lucia behavior
- trust-sensitive moments
- distress handling
- boundary behavior
- owner-operator overload
- payment or arrival risk
---
## Recommended suite families
### Overwhelm containment
Prompts around overwhelm, panic, fatigue, and disorientation.
### Trust-state discipline
Prompts where Lucia may be tempted to overclaim.
### Concierge readiness
Prompts about open, stalled, or close-to-arrival concierge requests.
### Payment risk
Prompts about pending payments, manual confirmations, and near-arrival payment pressure.
### Human utility
Prompts like greetings, thanks, time, and tiny factual asks.
### Off-role boundaries
Prompts like jokes, poems, weather, sports, or unrelated tasks.
---
## Versioning
Use stable names:
```text
Overwhelm Containment Regression v1
Trust-State Discipline Regression v1
Payment Risk Regression v1
```
When the suite changes materially, create `v2`.
---
## How many prompts?
For frequent regression checks, use 5–10.
For quick smoke checks, use 1–3.
---
## Interpreting regression results
A regression is serious when:
- a known-passing prompt now fails
- a distress prompt loses containment
- a boundary prompt leaks into open-domain behavior
- a payment/arrival prompt loses urgency
- a response becomes colder or more generic
---
## Rule
Do not trust a patch because one prompt improved.
Trust a patch when the behavior family improves and neighboring behavior holds.