The vocabulary of agentic marketing, defined.

Plain-English definitions of conversion tracking, marketing measurement, and agentic marketing terms — each one an atomic answer linking to where it goes deeper.

C

Click ID (gclid / fbclid / wbraid)

A click ID is a unique URL parameter an ad platform adds at click time (gclid, fbclid, msclkid, ttclid) so a conversion can be matched back to the exact ad click.

Consent mode (v2)

Consent mode is the API that tells Google tags what a visitor consented to. Version 2 added two signals, required for EEA ads measurement since March 2024.

Conversions API (CAPI)

The Conversions API is Meta's server-to-server channel for conversion events: a second delivery route for the same events the pixel sends from the browser.

Cookie lifetime / ITP

Cookie lifetime is how long a cookie actually survives in the browser: Safari's ITP caps script-set cookies at 7 days, sometimes 24 hours, whatever expiry you set.

Cookieless tracking

Cookieless tracking is measurement that doesn't depend on third-party cookies: first-party data, server-side events, hashed-identifier matching, and modeled conversions.

Cross-domain tracking

Cross-domain tracking keeps a visitor recognized as one session when they move between domains you own, by passing the identifier across the domain boundary.

E

Enhanced conversions

Enhanced conversions sends hashed first-party data (email, phone, or name plus home address) with your Google Ads conversion tags, recovering matches cookies lose.

F

First-party data

First-party data is data you collect from your own audience on your own surfaces (site events, CRM records, order history) under your direct consent.

I

Identity resolution

Identity resolution (user stitching) connects events and records carrying different identifiers (hashed email, user ID, click ID, device ID) into one person.

L

LTV & LTV:CAC ratio

Customer lifetime value (LTV) is the total value a customer generates over the whole relationship; LTV:CAC divides it by the cost to acquire that customer.

M

Meta pixel

The Meta pixel is Meta's JavaScript snippet that reports website events (PageView, Purchase, Lead) from the visitor's browser to Meta for measurement and optimization.

O

Offline conversions

Offline conversions complete away from your website and are imported back into the ad platform afterward, joined to the original ad click by click ID or hashed email.

S

Server-side tagging (sGTM)

Server-side tagging runs your tag manager on a server you control, so events reach ad and analytics platforms from your infrastructure instead of the visitor's browser.

Server-side tracking

Server-side tracking sends conversion and analytics events from a server you control instead of the visitor's browser: a more durable route for the same events.

Signal quality

Signal quality is the fitness of your conversion data as an input to automated bidding: complete, deduplicated, on time, and carrying real values.

Smart Bidding

Smart Bidding is Google Ads' auction-time automated bidding (tCPA, tROAS, Maximize conversions, Maximize conversion value), setting each bid from the conversion data you feed it.

T

The tracking bottleneck

The tracking bottleneck is the point where conversion signal quality caps everything downstream: bidding, attribution, and MMM can't be better than the data they're fed.

Third-party cookies

Third-party cookies are cookies set by a domain other than the one you're visiting: the basis of cross-site ad targeting, blocked by Safari and Firefox, kept by Chrome.

Tracking pixel

A tracking pixel is a tiny image or script that fires an HTTP request on a pageview or event, carrying the URL, referrer, timestamp, and identifiers to a collection server.

U

UTM parameters

UTM parameters are the standard URL query parameters (utm_source, utm_medium, utm_campaign, utm_term, utm_content) that attribute a visit to its campaign.

V

Value-based bidding

Value-based bidding is automated bidding that optimizes toward conversion value instead of conversion count: tROAS and Maximize conversion value on Google Ads.