Budget

Budget controls let you define spend limits and track consumption against them. They run as a preflight check before the agent acts, so an action that would breach a configured limit is stopped before it executes.

Navigate to Policies > Spend limits.

Budget Envelopes

Envelopes are named spend buckets with limits. Each envelope defines:

• A name (e.g., "Q2 Brand Awareness") and optional description
• A total budget — the cap for the period
• A period — daily, weekly, monthly, quarterly, or lifetime, with a period start and optional end
• A currency
• An alert threshold — the percentage of the cap that triggers an alert
• A breach action — what happens when the cap is reached: block, warn, or notify
• An optional scope — the action types and action names the envelope applies to

Cesteral tracks spent to date, remaining, and utilization percentage against each envelope.

Creating an Envelope

1. Click New Envelope
2. Enter a name and total budget
3. Select the period and currency
4. Set the alert threshold and breach action
5. Optionally scope it to specific action types or names
6. Click Save

The envelope becomes active immediately and is checked by the budget preflight on every relevant action.

When a Cap Is Reached

The breach action determines what happens as spend approaches and reaches the cap:

When the alert threshold is crossed, an alert fires (alertTriggered is set) regardless of the breach action.

Interval Spend Caps

In addition to a period envelope, you can attach interval spend caps that limit spend within a rolling daily or weekly window. Each cap tracks the current interval's spend and carries its own breach action, so you can — for example — set a generous monthly envelope but still block any single day from spending more than a fixed amount.

The Spend Circuit-Breaker

When recorded spend on a block envelope passes its cap, the budget circuit-breaker engages and notifies you. It blocks new budget increases, new campaigns and resumes — whatever the action is labelled — and lets pauses, budget decreases and actions that change no budget through, so you can still stop the spend.

The circuit-breaker blocks new budget-increasing actions on breach — it does not autonomously pause running campaigns. Spend already in flight on the ad platform continues until you pause or cut it; the breaker stays armed until the breach is cleared or overridden.

How Budget Limits Feed Guardrails

Budget evaluation runs as a preflight and surfaces its result to the guardrail engine under context.budgetPreflight, so your guardrails can reference budget state directly when deciding whether to block an action.