# Health Checks

> A mechanism that reports whether an instance and the dependencies it needs are ready to serve, so routing and restarts can act on it.

Record: `architecture:health-checks`
Kind: mechanism
Layer: [Correctness Core](https://banes-lab.com/records/layer/correctness-core.md)
Severity: contextual
Scope: service, deployment, runtime
Canonical: https://banes-lab.com/ontology#architecture-health-checks

Listed in [Architecture principles](https://banes-lab.com/api/records/architecture.md), after [Self-Healing Architecture](https://banes-lab.com/records/architecture/self-healing-architecture.md) and before [Failover](https://banes-lab.com/records/architecture/failover.md).

## Repair

- Refactored by: Add Liveness/Readiness/Dependency Checks
- Detected by: missing or shallow health endpoint
- Violated by: traffic routed to unhealthy instance
- Measured by: health-check accuracy
- Enforced by: deployment policy

## Requires

- [Observable Health Criteria](https://banes-lab.com/records/lexicon/observable-health-criteria.md)

## Reinforces

- [Self-Healing Architecture](https://banes-lab.com/records/architecture/self-healing-architecture.md)
- [Load Balancing](https://banes-lab.com/records/architecture/load-balancing.md)

## Enables

- [Readiness/Liveness Routing](https://banes-lab.com/records/lexicon/readiness-liveness-routing.md)

## Conflicts with

- [Blind Routing](https://banes-lab.com/records/lexicon/blind-routing.md)

## In tension with

- [False Positives](https://banes-lab.com/records/lexicon/false-positives.md)

## Tensions

- [Health Checks / False Positives](https://banes-lab.com/records/tension/false-positives-health-checks.md)

## Severity

- [contextual](https://banes-lab.com/records/vocabulary/severity-contextual.md)

## Category

- [Self-Healing / Recovery / Deployment Safety](https://banes-lab.com/records/architecture-category/self-healing-recovery-deployment-safety.md)

## Required by

- [Service Discovery](https://banes-lab.com/records/architecture/service-discovery.md)

## Linked from

- [Runtime Discovery / Dynamic Binding](https://banes-lab.com/ontology/principles/architecture-category-runtime-discovery-dynamic-binding.md)
- [Scalability / Performance / Optimization](https://banes-lab.com/ontology/principles/architecture-category-scalability-performance-optimization.md)
- [Plugin / Extensibility / IoC](https://banes-lab.com/ontology/principles/architecture-category-plugin-extensibility-ioc.md)
- [Self-Healing / Recovery / Deployment Safety](https://banes-lab.com/ontology/principles/architecture-category-self-healing-recovery-deployment-safety.md)
- [Core Vocabulary](https://banes-lab.com/ontology/lexicon/lexicon-category-core-vocabulary.md)
- [Self-Healing / Recovery / Deployment Safety](https://banes-lab.com/ontology/lexicon/lexicon-category-self-healing-recovery-deployment-safety.md)
- [Severity levels](https://banes-lab.com/ontology/schema/the-vocabulary-severity.md)
- [The resolutions](https://banes-lab.com/ontology/schema/the-resolutions.md)