KEYWORDS: budget, spend, spending, money, dollars, $, quarter, monthly, allocation, cost, funds, cap, limit

            CREATION TYPES (these are not required for cap-only updates):
            - Lead Generation (default): goal=CPL, groupMetric=CPL, optimizerFormula=CPL_2 (or CPC_2), autoPauseConfigurationId=14, enableBooster=true. Requires benchmark and groupMetric. Dates follow budgetType, not the goal (see DATE RULES): FIXED_BUDGET sends startDate AND endDate, MONTHLY_RESET sends neither.
              • MQL variant (the plan's KPI is MQLs / cost per MQL): goal=CPL, groupMetric=CPMQL, optimizerFormula=MQL, benchmark = the cost-per-MQL target. MQL is NOT a value of goal or groupMetric; the platform rejects it. Keep the CPL goal and express MQL through groupMetric=CPMQL + optimizerFormula=MQL.
              • Influenced-opportunity variant: goal=CPL, groupMetric=CPL, optimizerFormula=INFLUENCED_OPP. This is a supported platform formula, not cost per lead. Preserve it on existing groups.
            - Brand Awareness: goal=CTR, autoPauseConfigurationId=9, enableBooster=false, budgetType=MONTHLY_RESET. Two formula variants:
              • CPC variant: groupMetric=CPC, optimizerFormula=CPC_2 (benchmark is a CPC target, e.g. 10)
              • CTR variant: groupMetric=CTR, optimizerFormula=CTR (benchmark is a CTR target in basis-points style, e.g. 10000)
              budgetRedistributionStrategy may be PERFORMANCE or PACING_ONLY. MONTHLY_RESET: omit BOTH startDate and endDate.

            WARNING: BUDGET-GROUP TYPE MUST FOLLOW THE CAMPAIGN GOAL (do not mix):
            - A CPL / Lead Generation campaign (campaignType "Lead Gen") REQUIRES a compatible Lead Generation budget group with goal=CPL. Its confirmed optimization metric and formula follow the selected variant above; cap-only updates preserve the existing variant.
            - A Brand Awareness campaign (campaignType "Brand Awareness") REQUIRES a Brand Awareness budget group: goal=CTR, enableBooster=false, budgetType=MONTHLY_RESET, autoPauseConfigurationId=9 (CPC or CTR formula variant per SUPPORTED TYPES above).
            - NEVER attach a Brand-Awareness (CTR) budget group to a CPL campaign, or a Lead-Generation (CPL) budget group to a Brand Awareness campaign — the optimizer goal must match the campaign's objective. If the campaign goal is unknown, confirm it before creating the budget group.

            MONTHLY CAP ONLY: use data containing only id and monthlyCap, e.g.
            {"id": 16900, "monthlyCap": 5000}. Read the exact existing group first.
            This update preserves its saved optimizerFormula, goal, metric,
            benchmark, booster, funnels, dates and campaign membership, including
            INFLUENCED_OPP and formulas outside the creation choices below.
            Do not resend creation defaults or convert the group to CPL or MQL.
            A zero cap is allowed, but the platform rejects caps below already-spent
            money; report that failure without changing optimization or bypassing it.
            Verify budget_update_verification.verified before claiming success or
            continuing to another group. If false, stop without retry or rollback.

            To UPDATE other settings: include 'id' with the budget group ID.
            To CREATE: omit the 'id' field.
            Pass all fields inside the `data` object. Dates must be ISO 8601 UTC with exactly 3 ms digits, e.g. 2026-01-15T12:00:00.000Z (format example only — compute the real values).

            DATE RULES FOR CREATION OR EXPLICIT SCHEDULE CHANGES:
            Cap-only updates preserve stored dates, including historical dates;
            do not replace them with a new flight or apply creation date rules.
            - startDate and endDate travel TOGETHER: send both or neither. The platform rejects one without the other with 400 VALIDATION_DATE ("End Date can not be empty" / "Start Date can not be empty"). budgetType decides which: FIXED_BUDGET = both required; MONTHLY_RESET = omit both. This holds for EVERY goal, CPL included: a Lead Gen group with a monthly budget is MONTHLY_RESET with no dates at all, never MONTHLY_RESET plus a startDate.
            - You do NOT inherently know today's date. If you are not already certain of it, call get_current_date FIRST and anchor every rule below to that real value — never guess.
            - The endDate MUST ALWAYS be in the future (strictly after today's real date).
            - NEVER set an endDate that is today or in the past — this will cause the budget group to be immediately expired.
            - "this month" → endDate = the last day of the current month. "this quarter" → endDate = the last day of the current quarter. "next month" / "next quarter" → compute relative to today's real date.
            - If the user provides a specific end date that is in the past, WARN THEM and ask for a valid future date. Do NOT submit a past endDate.
            - startDate can be today or in the future, but never in the past for new budget groups.

            REMARKS:
            - If the user doesn't EXPLICITLY states that their budget is by month or MONTHLY, then use FIXED_BUDGET as budgetType.
            - In other words, the default value is FIXED_BUDGET unless the user explicitly says MONTHLY or BY MONTH.
            - IF the user says "this month" then also use FIXED_BUDGET and start date should be today, end date should be the last day of the month.
            - When you use FIXED_BUDGET (fixed-date) but the user's timing expectations/goals are NOT clear, ASK for an explicit start-date and end-date before creating — do not silently invent a date range. Only skip the question when the dates are already unambiguous (e.g. the user gave a range, or said "this month"/"this quarter").
            - monthlyCap is the user's money: when the user has NOT explicitly stated a budget / monthly cap (or confirmed a figure you proposed), ASK for it before creating — do not silently invent a cap. This applies to campaign-creation flows too: a budget group needed by a new campaign still requires a user-chosen cap. Same when an update would change monthlyCap.
            - If the user says "set a monthly budget of $X" or equivalent then use MONTHLY_RESET as budgetType (MONTHLY is NOT a valid value, the platform rejects it)
            - Before an update, refresh the information by using get_budget_group to avoid overwriting fields unintentionally.
            - The campaign doesn't need to be in a launched state for its budget group to be updated.

            WHEN TO USE:
            - User wants to create a new budget group with specific settings
            - We're creating a campaign and need to set up its budget group.
            - User requests to update an existing budget group with new parameters
            - User requests to update the budget of a campaign

            INTEGRATION WITH OTHER TOOLS:
            - If the ID for a budget group update is unknown there are a few options:
              - if you have the campaign name, use search_campaigns_by_name. In its response, `$.optimizationGroup.id` is the budget group ID.
                - From search_campaigns_by_names's response, you get the property `$.optimizationGroup.id`. That's the budget group ID.
            - You can also use get_budget_group if you have the budget group name to retrieve its ID.

            Anchor every date calculation to the REAL current date — if you are not certain what today is, call get_current_date before computing start/end dates.