Metric definition
Measure TTH from authenticated halt signal receipt to confirmed downstream action cessation, not merely UI acknowledgement.
What is Time-to-Halt (TTH)?
Time-to-Halt (TTH) defines how quickly an automated system must stop after a halt request.
Glossary anchor
Time-to-Halt (TTH)
Connect the explainer to the canonical definition for citations and shared language.
Time-to-Halt (TTH) measures the latency between a user or operator requesting a stop and the system actually halting. It turns stoppability into a measurable service-level requirement with clear thresholds.
Teams use TTH to shrink the window for unwanted actions and to verify that halt controls are not merely cosmetic.
A payments platform sets a five-second TTH target so any queued transfer stops within five seconds of a user hitting the halt control.
Implementation
Distinct implementation signals
Unique operational detail to help this concept stand on its own in policy, procurement, and review workflows.
Common failure pattern
Teams monitor average TTH while tail latency remains dangerous; enforce p95/p99 thresholds for high-harm action classes.
Evidence to ship
Provide endpoint-level TTH histograms, dependency breakdowns, and incident reviews for every threshold breach.
Standard
STD-01 — The Temporal Bill of Rights
Map TTH targets to the timing obligations in Article I and Article III.
Binding
Binding vectors
Operationalize TTH targets in procurement and release gate checklists.
Evidence pack
STD-01 evidence pack
Use runtime logs and halt receipts to validate time-to-halt performance.
What is a reasonable TTH target?
Set TTH targets based on the harm window of the action: higher-risk actions demand sub-second or single-digit second stops.
How do we measure TTH in practice?
Measure from the time the halt request is issued to the moment all downstream actions cease and the receipt confirms the stop.