Formats and endpoint aliases

Three tables. The narrative version is in one document per operating system.

Document extensions

The allowlist of extensions rescriptum will pick up from a store. Anything else is ignored — txt is deliberately not on the list, so a stray notes file next to your answers never becomes a candidate.

Extension	Family	Layering	Content-Type
`toml`	TOML	structural merge	`text/plain; charset=utf-8`
`yaml`, `yml`	YAML	structural merge	`text/yaml; charset=utf-8`
`json`, `ign`	JSON	structural merge	`application/json`
`xml`, `autoyast`, `unattend`	XML	structural merge, by element	`application/xml; charset=utf-8`
`ks`, `cfg`, `preseed`, `seed`, `ipxe`	text	concatenation in layer order	`text/plain; charset=utf-8`

The family is what the log line’s format= field reports, so ks and preseed both appear as format=text. The extension is what an endpoint filters on, and what check needs in order to pick the right validator.

Endpoint aliases

A path segment naming one of these restricts the answer to documents with the listed extensions. Any segment of the path may name it, so /rhel/ks, /ks and /provision/rhel/node.cfg all restrict to kickstart.

Segment	Serves	Typical use
`proxmox`, `pve`, `toml`	`.toml`	Proxmox VE
`debian`, `preseed`	`.preseed`, `.seed`	Debian preseed
`rhel`, `centos`, `fedora`, `alma`, `rocky`, `kickstart`, `ks`	`.ks`	kickstart
`ubuntu`, `autoinstall`, `cloudinit`, `nocloud`, `yaml`, `yml`	`.yaml`, `.yml`	Ubuntu autoinstall, cloud-init
`flatcar`, `coreos`, `ignition`, `ign`	`.ign`, `.json`	Ignition
`suse`, `opensuse`, `autoyast`	`.autoyast`, `.xml`	AutoYaST
`windows`, `unattend`	`.unattend`, `.xml`	Windows unattend.xml
`json`	`.json`, `.ign`
`xml`	`.xml`
`cfg`	`.cfg`
`ipxe`	`.ipxe`

A segment naming none of these constrains nothing, which is why /answer keeps working exactly as it always has.

Two traps in this table

Filtering is on the extension, not the family. .ks and .preseed are both text documents; filtering by family would let a preseed answer /rhel/ks.
seed is deliberately not an alias. s=http://server/seed/ is an ordinary NoCloud seed URL, and it serves YAML. An alias has to be specific enough that nobody reaches it by accident. (The .seed extension still exists, and /debian/ serves it.)

Control keys, per format

Stripped before the answer is sent.

Format	Spelling
TOML	top-level `extends = "base"`, `members = […]`, `[match]` table
YAML	top-level `extends:`, `members:`, `match:`
JSON	top-level `"extends"`, `"members"`, `"match"`
XML	`<answer-meta extends="base"><member>…</member><match k="v" /></answer-meta>`
Text	`# answer: extends <name>` · `# answer: member a, b` · `# answer: match k=v k2=v2`

Text directives also accept // as the comment marker. match takes space-separated key=pattern pairs; member a comma-separated list. Ordinary comments in a text document are served — only # answer: lines are removed.

Merge semantics

	Structural formats	Text formats
Maps / objects / elements	merge recursively	—
Scalars	higher layer replaces	—
Arrays / lists	replace, never append	—
Whole document	—	concatenated in layer order

XML pairs siblings by element name plus a discriminating attribute — name, id, key, alias, pass — and honours config:type="list". Declarations, doctypes, namespaces and attributes survive a merge; original indentation and comment placement do not.

Validators `check` can call

Format	Tool	Invoked as
`toml`	`proxmox-auto-install-assistant`	`validate-answer <file>`
`xml`, `autoyast`, `unattend`	`xmllint`	`--noout <file>`
`ks`	`ksvalidator`	`<file>`
everything else	—	none exists

A tool that is not on PATH is reported once as a note, never as a failure.