Delivery logs: debug CAPI like you debug API requests
Every conversion should leave an HTTP trail. Delivery logs show platform responses, payloads, and retries — so you fix match issues before wasting ad spend.
- delivery logs
- debugging
- observability
- dashboard
Problem: Marketing says tracking is broken. Engineering cannot reproduce. Nobody knows if Meta returned 200 or 400 for last night's purchases.
What delivery logs show
Each canonical event gets a row per destination: HTTP status, latency, error body summary, and mapped platform event name. Filter by Purchase, SignUp, platform, or status code.
This replaces guessing from pixel helpers or delayed ads manager UI.
Common 400 causes
Invalid or expired access token, wrong conversion action ID, missing currency on value events, malformed email hash, and duplicate payloads without eventId dedup on the platform side.
Fix credentials in Configure, replay test events, confirm 200 in logs.
Deploy-day workflow
After shipping auth or checkout changes, fire one test conversion per event type. Check logs before enabling campaigns.
Compare log volume to internal signup/purchase counts for the same hour — large gaps mean capture regression, not ad performance.
vs platform UIs
Meta Test Events and Google diagnostics are useful but laggy and session-scoped. Logs are the continuous audit trail across all destinations.
Sources
Official documentation and references cited in this article.
More in Product
Using PostHog and TrackStack together
PostHog answers product questions; TrackStack delivers conversions to ad platforms. Here is how to run both without duplicate scripts, conflicting proxies, or split event schemas.
Read postDomain allowlisting for public API keys
TrackStack public keys ship in client bundles. Domain allowlisting restricts which origins can send events — a basic security control every production app should configure.
Read postConfigure: map canonical events to ad platforms
The Configure split separates credentials, per-platform event allowlists, and checklists from generic settings — so you ship destinations without tag manager indirection.
Read postReady to fix your conversion pipeline?
Install the TrackStack SDK, route events to Meta and Google, and verify delivery from one dashboard.