Guardrails
Guardrails are eligibility rules on a treatment that determine which users are allowed to receive it. A user must satisfy all guardrail conditions to be eligible for a given treatment.
Guardrails let you control targeting precisely — ensuring the right message reaches the right audience without over-messaging or serving irrelevant content.
How Guardrails Work
Guardrails are defined using Data Fields. Each guardrail is a condition expressed as a comparison:
| Operator | Example Condition | Meaning |
|---|---|---|
> | days_since_signup > 7 | User signed up more than 7 days ago |
= | subscription_tier = "premium" | User is on the premium tier |
>= | cart_item_count >= 1 | User has at least one item in their cart |
!= | country != "JP" | User is not in Japan |
in | device_type in ["ios", "android"] | User is on a mobile device |
When a treatment has multiple guardrail conditions, all conditions must be satisfied for the user to be eligible.
Guardrails vs. Goals
Guardrails control who can receive a treatment. Goals define what outcome the treatment is trying to drive.
| Concept | Controls | Example |
|---|---|---|
| Guardrail | Eligibility — who sees it | "Only users with cart_item_count >= 1" |
| Goal | Outcome — what you're optimizing for | "Increase purchases" |
Treatment Selection with Guardrails
When a user makes an API request for treatments, Auxia first filters all Live treatments down to those the user is eligible for (based on guardrails). It then applies its decisioning algorithms to select the optimal treatment from the eligible set.
This means guardrails define the candidate pool — Auxia's algorithms make the final selection within that pool.
Frequency Caps and Suppression
In addition to attribute-based guardrails, Auxia also supports:
- Frequency caps — Limit how often a user can receive a specific treatment (e.g., no more than once every 3 days).
- Post-interaction suppression — Automatically suppress a treatment for a user after they have clicked or dismissed it (e.g., do not re-show a dismissed treatment for 3 days).
These are configured at the treatment level and work alongside guardrail conditions.
Related Concepts
- Treatments — guardrails are set on individual treatments
- Data Fields — the data used to evaluate guardrail conditions
- Journeys — journeys group treatments; guardrails apply per treatment
- Goals — the outcome that eligible treatments optimize toward
How-to guides: Managing Treatments