PublicSchema wizard prompts

bregctl init <DEST> --from publicschema, given neither --starter nor --selection, asks for a selection at a terminal. The answers become the same ModelSelection document a starter ships or --selection reads, so nothing downstream can tell the three apart. This page records the nine questions in the order they are asked.

Contract status

bregctl is pre-1.0 adopter tooling and sits outside any frozen runtime contract. These prompts can change before a compatibility promise covers them. The page is hand-written from crates/registry-bregctl/src/init_from_model/wizard.rs, not generated.

Every prompt, every line printed beside one, and the review are written to standard error. Standard output carries only the final report, so a script that captures standard output still gets a clean result even when the command runs at a terminal. A prompt is raised only when both standard input and standard error are terminals.

Nothing is written to disk until the last question is answered. The selection is resolved against the embedded model before the review, so a refusal the model forces is reported before you are asked to confirm.

Registry identifier

Registry identifier, with the help line lowercase letters, digits, and hyphens; it names the registry in its IRIs, scopes, and the catalogue. There is no default.

An answer must be 1 to 64 characters, start with a lowercase letter, and use only a-z, 0-9, -, and _. The prompt applies the same grammar to the five names the project derives from the answer, the publisher (-authority), the data service (-api), the public service (-service), and the -operator and -reader principals, so a length that fits the identifier but not its derived names is refused at the prompt rather than by the compiler afterwards. A refusal is shown inline and the question is asked again.

Registry title

Registry title, with the help line the name a reader sees; enter to keep the default. The default is the identifier read back in words, so household-registry offers Household Registry. Enter alone keeps it. A title that is empty or only whitespace is refused.

Which concepts become entities?

A multi-select with the help line space to toggle, type to filter, enter to confirm. At least one concept must be chosen.

The list holds every concept that is not abstract and carries at least one property the derivation could keep, ordered by the schema file that defines the concept and then by concept name. An option reads as the concept’s label, its schema file in parentheses, and the first sentence of its description cut to 60 characters: Person (publicschema-identity): The unique individual human being who is a subject of record….

Nothing starts ticked.

Which concepts connect what you chose?

A multi-select with the help line space to toggle, type to filter, enter to confirm; enter alone adds none.

The list holds the concepts you did not choose that carry at least two single-valued properties pointing at concepts you did. Each option names those properties and what they point at: Group Membership (publicschema-misc): group is a Household, person is a Person. Concepts whose every link fits exactly one chosen concept come first, then the rest by concept name, and each concept’s links read in property order. Nothing starts ticked, and enter alone adds none; a registry of unrelated collections is a legitimate answer.

The prompt is skipped when the model offers no such concept. When you chose two or more concepts and some of them have nothing in the model to connect them, one line is printed first naming those concepts, or saying that nothing in the model connects any of them to one another. That line is printed whether or not a prompt follows.

Which properties of <Title> become fields?

One multi-select per chosen concept, in the order the concepts were chosen, with connectors last. The help line is space to toggle, type to filter, enter to confirm, and at least one property must be chosen.

The list holds every property the derivation can turn into a field for this selection. An option names the property, the shape its field takes, sensitive or restricted where the model rates it so, and how many of the systems the model tracks already record it: date_of_birth: date (6 of 6 systems).

An option starts ticked when any of three things holds:

• The model marks the property required.
• At least 60% of the systems the model tracks already record it.
• It is a single-valued reference to another concept you chose, which is usually why the concept carrying it was chosen at all.

A property the derivation cannot carry is not offered. Those properties are named on one line before the prompt, opening Not offered for <Title>:, each with the derivation’s own sentence saying why and what to do instead.

Which entity does <Concept>.<property> point at?

A single select with the help line type to filter, arrows to move, enter to select, listing the entity identifiers of the chosen concepts whose kind fits the property, in the order chosen.

It is asked only where more than one chosen concept fits a single-valued reference, and only after every concept’s properties are settled, because a property may point at a concept chosen after the one carrying it. Where exactly one concept fits, the reference is settled without a question.

Keep the default identifiers and routes?

A yes-or-no question defaulting to yes, with the help line they name the collection routes, the record identifiers, and the fields a client reads. One line per entity precedes it, showing what that entity would be called: person: route persons, identifier field person-code.

Answering yes keeps every default and asks nothing more. Answering no asks three questions per entity, in turn, each with the help line enter to keep the default:

Question	Default
Entity identifier for <Concept>	The concept in kebab case
Collection route for <Concept>	The plural of the entity identifier answered before it
Identifier field for <Concept>	The entity identifier with -code appended

Each answer is held to the identifier grammar. An entity identifier or a route another entity of the same run already carries is refused inline with `<value>` is already taken by another entity, because the resolver refuses such a selection and the prompt refuses it while you are still there to answer again. An answer left at its default is left out of the written selection.

Which code lists should the project list in full?

A multi-select with the help line space to toggle, enter to confirm; an unticked list is carried as a bounded code instead, listing every enumeration a chosen property draws on, by model name, with its size: Marital Status (6 values).

An enumeration of at most 300 values starts ticked, which is the size rule the derivation applies to a selection that says nothing. The prompt is skipped when no chosen property draws on an enumeration. Only an answer that differs from the size rule is written into the selection’s vocabularies list.

Derive the project from this selection?

The selection your answers describe is printed as YAML, followed by one line naming any entity no field connects to another, and then a yes-or-no question defaulting to yes, with the help line the document above is written into the project beside what it derives.

Answering yes derives the project. Answering no writes nothing and reports init.selection.cancelled.

Cancelling, and running without a terminal

Situation	Report
Esc or Ctrl+C at any prompt, or no at the review	init.selection.cancelled: cancelled at a prompt; nothing was written
A prompt cannot be raised for any other reason	init.selection.prompt: a question could not be asked, followed by the library’s own message
No terminal on standard input or standard error	init.selection.missing: `init --from publicschema` asks its questions at a terminal; without one, pass `--selection <FILE>` or `--starter <NAME>`

Nothing is written in any of the three cases, so there is nothing to undo. Pass --starter or --selection to derive without a terminal.

Next

• Derive a registry from PublicSchema to run the same derivation from a shipped selection instead.
• How a registry is derived from a model for the rules the answers feed.
• bregctl init --help for every other flag init accepts.