Reuse one ad across every ad group

Search campaigns usually run one ad in every ad group — one ad group per keyword theme, the same creative everywhere. So the same 12 headlines and 4 descriptions get pasted into ad after ad. Change one headline and you’re editing every copy by hand; miss one and the ads quietly drift apart.

Locals fix a repeated headline list, but here the whole ad body repeats — final URLs, headlines, descriptions, paths, all of it. An ad_template names that body once.

Declare the body once

A top-level ad_template "name" { … } block holds exactly an ad {} body:

ad_template "ublock_rsa" {
  final_urls = ["https://ghostery.info/ublock?utm_source=google&utm_medium=cpc&utm_term={keyword}"]
  responsive_search_ad {
    headlines = [
      "uBlock Gone? Try Ghostery",
      "uBlock Replacement Found",
      "Switch from uBlock Now",
    ]
    descriptions = [
      "Blocks ads, trackers & popups. Manifest V3 ready.",
      "The privacy suite millions of people trust.",
    ]
    path1 = "ublock"
    path2 = "ghostery"
  }
}

Attach it to each ad group

Each ad is still its own google_ads_ad_group_ad. Instead of an inline ad {} block, point it at the template:

resource "google_ads_ad_group_ad" "replacement_rsa" {
  ad_group = google_ads_ad_group.replacement.id
  status   = "ENABLED"
  template = ad_template.ublock_rsa
}

resource "google_ads_ad_group_ad" "chrome_rsa" {
  ad_group = google_ads_ad_group.chrome.id
  status   = "ENABLED"
  template = ad_template.ublock_rsa
}

resource "google_ads_ad_group_ad" "safari_rsa" {
  ad_group = google_ads_ad_group.safari.id
  status   = "ENABLED"
  template = ad_template.ublock_rsa
}

Three five-line stubs instead of three 30-line bodies. Edit the headline in ad_template.ublock_rsa once and bidsmith plan shows it landing on all three ads at the same time.

Adopting it on a live account is safe

Each ad keeps its own resource address, so folding existing ads onto a template is a pure source refactor: the body bidsmith sends is identical, and plan reports no changes. Nothing is recreated — your ads keep their history and review status.

An ad_template declared in one file can be referenced from any other — the same resolution rules as resources. Put the bodies that several campaigns share in one file (say templates.bid) and reference them from each campaign file:

resource "google_ads_ad_group_ad" "replacement_rsa" {
  ad_group = google_ads_ad_group.replacement.id
  template = ad_template.ublock_rsa   # declared in templates.bid
}

Vary the landing page per ad group

Often the creative is shared but each ad group points at a different landing page — homepage here, a comparison page there. You don’t need a separate template for each URL. Drop final_urls from the template and let every ad supply its own; path1 / path2 work the same way:

ad_template "ublock_rsa" {
  responsive_search_ad {
    headlines    = ["uBlock Gone? Try Ghostery", "uBlock Replacement Found", "Switch from uBlock Now"]
    descriptions = ["Blocks ads, trackers & popups. Manifest V3 ready.", "The privacy suite millions trust."]
    path2        = "ghostery"
  }
}

resource "google_ads_ad_group_ad" "chrome_rsa" {
  ad_group   = google_ads_ad_group.chrome.id
  template   = ad_template.ublock_rsa
  final_urls = ["https://ghostery.info/chrome?utm_term={keyword}"]
  path1      = "chrome"
}

resource "google_ads_ad_group_ad" "safari_rsa" {
  ad_group   = google_ads_ad_group.safari.id
  template   = ad_template.ublock_rsa
  final_urls = ["https://ghostery.info/safari?utm_term={keyword}"]
  path1      = "safari"
}

Anything you set on the resource (final_urls, path1, path2, final_url_suffix, custom_parameters) wins over the template; anything you leave out is inherited. The headlines and descriptions still live in one place. If a template omits final_urls, every reference has to provide one — validate catches any that forget.

Vary a headline or a tracking slug

final_urls and the paths are the common case, but an A/B pair usually differs in one headline too — and duplicating the whole body to change one string is exactly what a template is meant to prevent.

Anywhere in a template body, write input.<name> for a value the ad supplies:

ad_template "fb_rsa" {
  final_urls = ["https://ghostery.info/facebook?utm_content=${input.slug}"]

  responsive_search_ad {
    headline {
      text = input.headline_1
      pin  = "HEADLINE_1"
    }
    headline { text = "Block Facebook Ads" }
    headline { text = "Free & Open Source" }
    description { text = "Stop the feed ads and the tracking behind them." }
    description { text = "Free forever. No account needed." }
  }
}

resource "google_ads_ad_group_ad" "fbads_block_rsa" {
  ad_group = google_ads_ad_group.fbads.id
  template = ad_template.fb_rsa
  inputs = {
    headline_1 = "Block Facebook Ads"
    slug       = "rsa_a"
  }
}

resource "google_ads_ad_group_ad" "fbads_getrid_rsa" {
  ad_group = google_ads_ad_group.fbads.id
  template = ad_template.fb_rsa
  inputs = {
    headline_1 = "Get Rid of Facebook Ads"
    slug       = "rsa_b"
  }
}

An A/B pair that used to be two full bodies is now two four-line resources, and the shared copy has one home.

A template’s parameters are simply the input. names its body uses — there is no separate list to declare, so the two can never disagree. bidsmith checks both directions:

Leave one out and validate says which template needs it and what to add.
Pass one the template never mentions and it says so too, with the names it does take. A silently-ignored headline2 is the kind of typo that only shows up in a performance report weeks later.

Values are checked where they land, not where they’re written: bind pin = input.slot to "TOPLEFT" and you get the same expected one of [HEADLINE_1, …] error as if you’d typed it inline.