Foundations.

Chain head, RPC latency, market-data index and pool indexer for every registered chain. When an index is down the citadel keeps reading directly from the chain and says so on the report.

ONLINE

Answered within the latency budget.

DEGRADED

Answered slowly, or the chain head is older than expected for its block time.

OFFLINE

No answer. Inspections that depend on it fail explicitly; on-chain reads continue where possible.