Metrics and Scoring

Tangle’s incentive programs can be driven by on-chain activity metrics. Metrics are optional: the protocol is designed so that core actions still work even if metrics recording is disabled or temporarily unavailable.

Core Components

• TangleMetrics: an on-chain activity recorder implementing IMetricsRecorder.
• Metrics hooks: best-effort calls from core contracts (wrapped in try/catch) that emit or aggregate activity data.
• InflationPool: a pre-funded TNT budget that can distribute TNT based on recorded metrics.
• ServiceFeeDistributor: distributes the restaker share of service fees and can record “exposure” scores that feed restaker rewards.

What Gets Recorded

Depending on what is configured on-chain, the protocol can record:

• Blueprint activity: blueprint creation and operator registrations.
• Service activity: service creation/termination, job calls, job completion success rates.
• Payments: total fees paid by customers.
• Operator liveness: heartbeats for active services.
• Slashing: executed slash events (and the slashed amount).

Restaker “Exposure” Scoring

For restaker rewards (from InflationPool), the protocol can compute an exposure score based on service participation:

• Exposure is tracked as a value × time measure (for example, USD-weighted exposure over the duration of a streamed payment).
• If a price oracle is configured, scoring can be normalized in USD terms; if not, the protocol falls back to raw amounts.

This scoring is separate from (and in addition to) per-asset APY-like incentives paid through RewardVaults.

Heartbeats and QoS

Operators (often via their blueprint manager) can submit service heartbeats to OperatorStatusRegistry. Heartbeats:

• Provide an on-chain signal of liveness for a given (serviceId, operator).
• Can mark operators offline for a service when heartbeats are missed.
• Are often used as part of off-chain monitoring, and may be referenced when proposing a slash.

Heartbeats do not automatically slash an operator by themselves; slashing requires an authorized on-chain proposal and execution.

Important Note on Budgets

Merit-based rewards only exist if InflationPool is funded with TNT. If it has a zero balance, there is nothing to distribute—even if metrics are recorded.