reliability-rules.md

Reliability validation rules

ServiceLevelIndicator and ServiceLevelObjective entities are checked by model validation, the engine behind the validate_event_model tool and the per-model pass of validate_project (see docs/how-to/repair-validation-findings.md). These checks only run for an indicator or objective listed in the EventModel's members; one that exists in the store but is not a member of any EventModel is never checked.

list_validation_rules is the live source of truth for titles, categories, and default severities; this page exists so the trigger conditions read without decoding the catalog from source.

Code	Severity	Subject	Trigger
SLI_CONNECTION_UNRESOLVED	Error	ServiceLevelIndicator.connection	The connection points at a missing slice, the wrong slice kind for the Connection variant, events not on that slice's edges, or an integration system the processor does not call.
SLI_JOURNEY_UNREACHABLE	Error	ServiceLevelIndicator.connection.journey	A journey's end event cannot be reached from its start event within the journey's scope.
SLI_CORRELATION_UNSOURCED	Error	ServiceLevelIndicator.connection.journey.correlate_on	A journey's correlate_on field is absent from the start event's or the end event's field list.
SLI_OUTCOME_UNREACHABLE	Error	ServiceLevelIndicator.measure.outcome_ratio	An outcome-ratio measure's good or bad event cannot terminate the connection, or either side is empty.
SLI_SIGNAL_MISMATCH	Error	ServiceLevelIndicator.signal	The signal cannot measure the connection or the indicator has no signal or measure at all.
SLO_THRESHOLD_MISMATCH	Error	ServiceLevelObjective.objectives	An objective carries a threshold for a non-latency indicator, or carries none for a latency indicator.
SLO_TARGET_RANGE	Error	ServiceLevelObjective.objectives	An objective's target ratio is not strictly between 0 and 1.
SLO_EXTERNAL_UNALERTED	Warning	ServiceLevelObjective.alert_policies	An externally committed objective has no alert policy watching it.
SLO_UNALERTED	Info	ServiceLevelObjective.alert_policies	An objective with no commitment, or an internal one, has no alert policy watching it.

SLI_CONNECTION_UNRESOLVED

A ServiceLevelIndicator's connection points at a slice that is missing or is the wrong slice kind for the Connection variant, names events not on that slice's edges (CommandHandling.events must be a subset of the command slice's emitted_events; Projection.source_events must be a subset of the read model slice's source_events), or names an integration system the processor does not list in calls. The measurement has nowhere real to attach.

SLI_JOURNEY_UNREACHABLE

A journey connection's end event cannot be reached from its start event within its scope (one storyboard, or the pooled slices of an EventModel's member storyboards). Reachability is structural, not storyboard order: an edge exists from a source event to a command's emitted events when a read model slice projects the source event and either an automation slice observes that read model and emits the command (a reaction chain) or a UI slice renders that read model for a persona who then issues the command from the same UI (a human handoff on one screen). This deliberately does not model a persona navigating to a different screen first, so a journey that only a cross-screen handoff can complete is conservatively reported as unreachable even though a human could still complete it by hand; narrow the journey or add the missing UI-to-slice pairing to clear the finding.

SLI_CORRELATION_UNSOURCED

A journey connection's correlate_on names a field absent from the schema of the start event or the end event. Without the field on both ends the two cannot be matched into one instance.

SLI_OUTCOME_UNREACHABLE

An outcome-ratio measure's good or bad event is not among the events the connection can end on: for command handling, the command slice's emitted_events; for a journey, the end event or any event reachable from the same start by SLI_JOURNEY_UNREACHABLE's reachability rule. Also fires when good or bad is empty, since a ratio with no numerator or no denominator side measures nothing. Connection kinds with no defined notion of termination (projection, reaction, display, integration) are not checked.

SLI_SIGNAL_MISMATCH

An event-timestamps signal needs an event marking the end of the span; display and integration connections render a screen or call outward with no such event, so event timestamps cannot source them. Also fires when the indicator has no signal or no measure at all.

SLO_THRESHOLD_MISMATCH

A ServiceLevelObjective's objective must carry a threshold when its indicator measures latency (the threshold says how slow is too slow) and must not carry one otherwise, since a ratio or completion measure has nothing to threshold.

SLO_TARGET_RANGE

An objective's target or time_slice_target ratio must be strictly between 0 and 1; 0 commits to nothing and 1 (or above) commits to perfection, neither of which is a budget.

SLO_EXTERNAL_UNALERTED and SLO_UNALERTED

Both report an objective with no alert_policies watching it; which one fires depends on commitment. SLO_EXTERNAL_UNALERTED is a warning for an objective with an External commitment, what a counterparty can hold the team to, since nothing pages before that commitment is breached. SLO_UNALERTED is informational for an objective with no commitment or an Internal one. The two are kept separate so an externally committed objective is not double-reported by both rules.