The field is there, the data is not: 1.55M postings on measuring ATS APIs before trusting them

A missing key throws an error somewhere you can see it. A key that is present and always empty returns cleanly and gets believed. BambooHR's `isRemote` is the second kind: the field ships in the payload, and across 50,616 postings drawn from 9,711 live BambooHR boards the census found it set exactly zero times ^[3]. That works out to roughly 5.2 postings per board ^[19], so this is not a few employers leaving a toggle alone. It is every employer on the platform, and the client that reads the field inherits a confident false negative with no error attached ^[3].

The thresholds the writeup uses are worth copying into your own audit. "Yes" means a fill rate of 99.5% or better, and "no" means the endpoint carries no such field at all, as opposed to the field being blank ^[23]. Those are different failures, and only one of them shows up in a schema dump.

Compensation is where shape beats rate. Four of the twelve carry it, which leaves eight with nothing to read ^[5][21]. Among the four, Pinpoint and Recruitee return minimum, maximum, currency and period as separate values, while Breezy and Ashby return prose, Ashby's with equity possibly folded into the top number ^[7][8]. The structured half has its own traps: Recruitee keeps the salary object populated with zeros when the employer skipped the field, so a naive reader publishes "0 USD hour" as a pay range ^[9], and European employers quote monthly, where normalising by twelve is a guess about holiday allowance and 13th-month pay ^[10].

The date arithmetic is small and unforgiving. Workday's `postedOn` converts "Posted Today" and "Posted 5 Days Ago" but not "30+" ^[12], which leaves 21.8% of its rows holding a phrase that cannot become a timestamp without invention ^[20]. Add the four platforms that publish no posting date at all ^[11] and the undated share is a property of the sources, not a gap you can backfill. On work arrangement, seven of the twelve give you nothing to read, so you are matching location strings, which misses "Anywhere" and fires happily on "Remote Support Engineer, London office" ^[14].

Collection has hazards before field measurement even starts. Workday's `total` saturates at 2000 while the API keeps serving rows past the end of the list, so the obvious loop, probing offsets until a page comes back empty, does not terminate ^[18]. Breezy answers 403 rather than 404 for a subdomain with no board ^[17]: read that as rate limiting and you back off from dead subdomains permanently, read it as fatal and you drop live boards ^[17].

The useful artefact here is not the endpoint list, which plenty of posts already publish ^[1]. It is a fill rate per field per platform, measured on live boards, with the measurement date attached. Put the rate next to the field name in your own schema and the silent false negative becomes a documented gap, which is the only version a downstream consumer can plan around.