v0.42.0 — What a composition can express

Every package pins "@markdoc/markdoc": "0.4.0" exactly: packages/runes, transform, content, svelte, editor, cli, language-server, plugins/places, site and plan-site. 0.4.0 was released in December 2023; 0.5.10 in September 2026, eleven releases later. Nothing in the plan or the git history records why the version is pinned. SPEC-123 and WORK-556 only call it "the pinned 0.4.0".The 0.4.0 → 0.5.10 source was read, not run. The changes that matter here:Worth having:

Indenting the content of a tag by a tab or four spaces breaks it today: the indented lines become a code block, with no error. Composition templates nest runes several levels deep, so this is the first thing an author of a definition runs into. Markdoc's allowIndentation tokenizer option fixes it, and SPEC-170 measured that it changes no existing parse.Markdoc.parse( is called directly in about 20 source files across packages and plugins. This item replaces them with one shared parse (SPEC-170 D1), so a page cannot render one way and validate, or preview, another.

A composition's content.type must be sequence or sections (packages/runes/src/lib/composition.ts). Five runes split their content on --- and need to address a field inside a zone: hero, feature, step, recipe and playlist. None of them can be a composition until the parser accepts type: delimited. The DelimitedModel type already exists (packages/types/src/content-model.ts), so this is a parser and resolver change, not a new model (SPEC-169 D1).

implicitSection exists on the sections model (packages/types/src/content-model.ts): when no section heading is found, all children become one section instead of preamble. The composition parser does not accept the key, so itinerary, whose conditional content model only exists to add it, cannot be expressed. Accepting it removes that rune's need for a conditional model (SPEC-169 D2, D3).

Today each iterates a list only when the field has an itemModel with an emitTag. A list whose items need no extraction, where each item's content is placed as it is, has no way in. That blocks steps, which takes its steps from headings or from an ordered list (SPEC-169 D4).

RuneConfig.sequence takes a literal ('numbered' | 'connected' | 'plain'), while sequenceDirection beside it takes { fromModifier, default } (packages/transform/src/types.ts). plot needs its sequence style keyed on its structure modifier, so it uses a postTransform (plugins/storytelling/src/config.ts), one of four left in the codebase. Giving sequence the same form deletes it (SPEC-147 Finding 1, implementation note 1).

Once WORK-645 allows indentation, SPEC-170 D5 sets the rule for when to indent: a block tag's content is indented only when it contains another block tag. A rule nobody can apply mechanically drifts, and no existing tool applies this one:

The documentation site is the largest body of refrakt content in the repository, and the first place a reader copies examples from. Once WORK-657 can apply SPEC-170 D5 mechanically, run it over the site, so nested runes read as nested and the examples teach the rule.