Catch silent Meta/TikTok CAPI failures before they tank your matching

- **Meta CAPI** (Conversions API) and **TikTok CAPI** are server-side advertising tracking systems that let brands send purchase/lead data directly to ad platforms, bypassing browser-based pixels. They are critical for ad measurement and for training the platforms' optimization algorithms. - When CAPI events fail silently (e.g., due to bad payload formatting, auth errors, or schema mismatches), the ad platform accepts the data without error but never uses it — a "silent fail." This degrades "matching" (the ability to link ad clicks to conversions), wasting ad spend and corrupting A/B tests. - This GitHub repository (`shopify-capi-validator`) is an open-source Shopify app that intercepts CAPI calls from a Shopify store, validates them against Meta's and TikTok's actual API schemas, and surfaces failures that the platforms themselves do not report. - The tool matters because most Shopify merchants using CAPI never know their data is being dropped, and the resulting performance degradation looks like a poor product or audience rather than a tracking bug.