ModelForge/docs/architecture/SERVICE_LEVEL_INDICATORS.md

Service-level indicators

An SLI is a first-class typed definition of a service or capability, its measurement, valid population, success condition and default window. An SLI does not contain an objective; objectives belong to versioned SLO policies.

Core definitions

Key	Population	Successful observation
platform.api.availability	control-plane and health requests since process start	2xx/3xx
gateway.availability	authenticated gateway requests in window	completed
gateway.latency.p95	completed gateway requests with latency	p95 below policy threshold
scheduler.correctness	persisted placement plans	typed admission, queue or refusal verdict
node.freshness	enabled production nodes	heartbeat age at most 90 seconds
runtime.success	terminal load/invoke/unload/health jobs	completed
migration.reliability	terminal migration plans	not failed/manual intervention

Capability definitions cover RAG success and latency plus Vision and Speech LAB success. The latter remain explicitly LAB. OCR has no quality or production SLO because M9/M11 quality and external evidence gates remain unsatisfied.

Project-facing health is derived only for actual scoped service clients and bindings. It reports project, capability, environment, client state, request/error counts and last use. ExampleRAG's production Ollama baseline is external to ModelForge and is not relabelled as a ModelForge production SLI. ExampleVision Vision shadow and ASR remain LAB.

Evaluation semantics

The evaluator selects only events inside the policy rolling window. It persists population, good and bad counts, observed value, freshness, policy identity and bounded source evidence. Latency evidence retains p50/p95/p99, while the initial policy evaluates p95.

Possible states are HEALTHY, AT_RISK, BREACHED, INSUFFICIENT_DATA, STALE and DISABLED. The minimum population is evaluated before health. No samples or too few samples can therefore never become green. Control-plane health, capability health and project integration health remain separate dimensions.