Dayparting is not on the targeting catalog
Targeting-keys returns 50 keys and no clock. Bid modifiers have 66 keys, including time_of_week and user_time_of_week. Checking one catalog was how we said dayparting did not exist.
Published 2026-09-09 · Search job: dayparting programmatic display
Dayparting for programmatic display on this seat is not a targeting key. It is a bid-modifier key. We said it was unavailable for three months because we checked the wrong catalog.
/rest/v2/ref/targeting-keys returns 50 keys across app_site, content, environment, exchange, geo, and platform. There is no clock anywhere. The first half of the old sentence was true: user_time_of_week is absent from this child seat's targeting-key catalog. The false step was concluding from that catalog that the capability does not exist.
Bid modifiers and delivery modifiers draw on a separate, wider vocabulary. OPTIONS /rest/v2/bid-modifiers returns terms[].targeting_key as a choice of 66 keys, including time_of_week, user_time_of_week, segment, user_id, ad_size, delivery, feed, and ip_address. None of those eight are in the 50-key targeting catalog.
Same class of error as custom_list
This is the same shape of mistake as the sentence that said placement and site excludes needed a custom_list the compiler could not emit. That sentence was derived from checking one endpoint. Placement and site are direct keys on app_site. The wrong sentence gated most of the waste the first real Supply Audit run found.
Here the one endpoint was targeting-keys. The clock lived on bid modifiers the whole time. Internal research notes already recorded "separate vocabulary from Buzz targeting-expression modules" and "time_of_week ranges" while our own operator docs claimed the opposite.
Verified live on September 3, 2026: every probe object was created and deleted, and the seat was left at zero modifiers. The capability is real. It is not a targeting expression.
What that means for trafficking
Eligibility and bid modification are different lists. Targeting decides whether the line item may bid. A bid modifier scales the bid when a term matches. An unmatched request keeps its bid unmodified, which is why a daypart must enumerate the hours to suppress rather than the hours to allow.
If you only read targeting-keys, you will keep writing "this seat cannot daypart." If you read bid-modifier OPTIONS, you will see 66 keys and a clock counted in minutes. Time of week is counted in minutes. Dayparting uses the viewer's clock.
Do not drop dayparting into the product as a replacement for the spend-spreading pacer. They answer different questions. Do not claim the capability is absent because the targeting catalog is silent.