What annotation companions record

On its own, a scan is only a picture of a page. It becomes useful through the reading made beside it. For a document that means a word-for-word transcription of exactly what it says, with a translation where the page is not in English. For a photograph, a drawing or a map it means a description of what it shows. A companion can also carry a short note on how the reading was made. Our method requires that any handwritten value a conclusion rests on, such as a name, a date or an address, have its reading provenance recorded and be read again by a second, independent external reader that has not seen the first reading, before it is registered. That is a working rule, not a claim that every companion records one: many companions note only who made the reading and what is still in doubt. The viewer shows the description, transcription and translation: enlarge a scan, open its Annotations panel and switch between the three tabs.

Not every part applies to every document, so coverage cannot honestly be counted as a single yes or no. A photograph needs a description and no transcription; a Dutch page needs a translation and an English one does not. A scan has a reading beside it when it has a description or transcription. A separate check asks whether every part that applies is also complete.

At the 10 September 2026 snapshot, something like nine hundred registered items carried at least one reading companion whose file is present. The exact figure moves as records are added, and it depends on whether accepted revisions count as separate companions. We have deliberately not reduced it to a single number or to a percentage of unique scans. We drop the earlier 938/771/167 coverage split here, because this deep dive did not define a denominator anyone could reproduce or say which kinds of item need which parts.

A coverage report that holds up needs a census part by part: which items are in scope, whether each needs a transcription, a translation or a description, and whether those parts exist. A missing companion may be backlog, a case where none applies, or a support defect. We do not fold all three into one percentage here. The proof-closure panel separately reports the simpler count of files present.

Most of what carries a reading looks like this household card from the population register. It is transcribed line by line, and beside it are recorded who made the transcription and which hard readings are still in doubt. At its head stands the cabinet-maker Cornelis Pelt, born in Rotterdam in 1856: