Render a VizCharter diagram from a spec and export it. Returns a PNG preview (look at it and iterate!), written file paths, embed snippets, and lint findings. Spec family 'architecture': { family:'architecture', title?, subtitle?, theme? (vizcharter-light|vizcharter-dark|aws), direction? ('AUTO' default — lays out both ways and keeps the tighter canvas | 'DOWN' | 'RIGHT'), nodes:[{id, icon? (registry id, see vizcharter_icons), label, sublabel?, parent? (container id), pin?:{x,y}}], containers:[{id, type:'region'|'account'|'vpc'|'subnet'|'az'|'layer'|'group', label, parent?}], edges:[{from, to, kind?:'sync'|'async'|'config'|'data', label?}], callouts?:[{n, at}], legend?:boolean }. Layer containers auto-rotate pastel tints; edge kinds get distinct styling and an auto legend. Spec family 'chart': { family:'chart', type:'bar'|'bar-stacked'|'bar-grouped'|'line'|'area'|'donut'|'pie'|'rose'|'venn'|'kpi', title?, theme?, width?, height?, categories?+series? (axis types), slices? (donut/pie/rose), sets?+overlaps? (venn, 2-3 sets), tiles? (kpi: {label, value, delta?, sublabel?}), options?: { showValues?, showLegend?, donutLabel? } } — same design tokens as diagrams. Spec family 'canvas' (infographics/posters): { family:'canvas', theme?, page?:{width,height,background?}, template?:{name, slots} (see vizcharter_templates; auto-sizes the page), layers?:[ {kind:'text', x,y,width?,text,style?,align?} | {kind:'shape', shape:'rect'|'circle'|'line', ...} | {kind:'icon', icon,x,y,size} | {kind:'chart', x,y,spec} | {kind:'arch', x,y,scale?,spec} | {kind:'svg', x,y,content} (raw-SVG escape hatch) ] — embed full chart/architecture specs into posters. ALL families accept an optional meta footer block, rendered as an elegant hairline band: { author?, org?, project?, version?, date?, classification? (outlined chip, e.g. 'Confidential'), source? (attribution line), note? } — use it when the user asks for authorship, versioning, dates, classification, or source attribution on a deliverable. Files land in /diagrams// including the re-editable .vizc.json source.

Update an existing diagram from its .vizc.json source. Applies an RFC 7386 JSON merge patch (objects merge recursively, null deletes a key, arrays replace wholesale) or a full replacement, then re-renders and re-exports to the same location. Returns the new preview and lint findings.

Re-export an existing diagram (.vizc.json source) to additional formats or scales without changing it. Note: new formats are added to the diagram's directory alongside existing exports.

Fuzzy-search the bundled official cloud icon packs — AWS, GCP, and Azure (1100+ icons). Returns icon registry ids (aws.lambda, gcp.bigquery, azure.kubernetes-services, …) to use as node icon values, with vendor category and aliases.

List built-in themes, or validate custom theme overrides (pass overrides) against the token schema including WCAG contrast expectations.

List the canvas poster templates with their slot schemas. Use with spec family 'canvas': { family:'canvas', template: { name, slots } } — the template computes layout and page size; add layers alongside to overlay extra elements.