Read ChatGPT Ads performance

Reports impressions, clicks, spend, conversions and the ratios derived from them (CTR, CPC, CPM, CPA, ROAS) for a window, broken down by campaign, ad group or ad — and compares every number with the equally long period immediately before it. Use when: the user asks how anything is doing, whether something is working, or what changed. Scope it with campaign_id, ad_group_id or ad_id; without any of them it reports the whole account. Do not use it for a brief or a report to keep or forward: that is generate_report_now (monitoring router), which covers every connected account and saves a page. Do not use it to find out what exists: that is chatgpt_list_campaigns. Daily numbers are noisy at small budgets, so prefer last_7_days or longer before recommending a change. The "last N days" windows end yesterday, so a partial day is never compared with a whole one. Returns spend as a decimal in the account currency and a percentage change per metric against the previous period. A dash in the change column means the previous period was zero, not that nothing changed. ROAS is only meaningful where the account reports attributed revenue; where it does not, it comes back empty rather than as zero. If the numbers are all zero, check chatgpt_list_ads for a review verdict and chatgpt_list_campaigns for a serving issue before concluding the ads are simply performing badly.