Server Side Conversion Tracking

Most "we already do CAPI" setups under-perform for one reason: the server events go out without click ids, so the platforms fall back to matching on hashed email alone. This skill gets the order right, capturing fbclid, ttclid, gclid and msclkid on first hit, persisting them server-side, carrying them across cross-domain funnel hops, and writing them onto the order before any event is sent. It then covers server-to-server reporting to Facebook, TikTok, Google and Bing, dedupe via shared event IDs, and a reconciliation check against your own order table. Its most useful output is the click-ID coverage number, which tells you quickly whether the chain is broken. The reference implementation it points to is self-hosted and Apache-2.0, though you'd still need to read the source to confirm how far it covers your particular funnel.

skills.sh installs: 120K
GitHub stars: 8
last updated: Oct 26, 2026

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Install

$ npx -y skills add autonnel/autonnel-skills --skill server-side-conversion-tracking --agent claude-code

Installs into .claude/skills of the current project.

Files

Server-Side Conversion Tracking

Browser pixels lose a large and unpredictable share of conversions to iOS tracking prevention, ad blockers, cookie lifetime limits and cross-domain hops. Server-side reporting fixes the reporting, which is what the ad platform's bidding model learns from. This skill covers the model, the setup order and how to verify it.

When to use

Ad platform reports fewer purchases than the store/database actually recorded
CPA looks like it got worse right after a tracking change, with no change in real sales
Setting up a new funnel that will receive paid traffic
Asked about CAPI / Events API / offline conversion import / click id passthrough
Attribution disagreements between platforms ("Facebook claims 40 sales, Google claims 30, we had 45 orders")