AI Gateway now shows where a session’s cache and spending went.
Vercel’s 18 October update adds a Sessions view to AI Gateway logs. It groups requests with their cost, models, providers and cached input; opening a session exposes the path across turns and any earlier providers. Use it to investigate a costly conversation before changing models. 1
Send a stable session identifier. Reuse providerOptions.gateway.sessionId or the x-session-id header across the conversation. Without one, grouping uses a fingerprint of its opening. Single-turn sessions are hidden by the default minimum-turn filter. 1
Session affinity prefers the previous provider to preserve cache reuse. Compare provider changes and cached input when investigating a bill; this view alone does not establish that a task produced an accepted result. 1
Inspect session-level routing and cache reuse before increasing the model budget.