ZeroWidth Napkin MCP Server

Creates a blank Napkin board — a sketch (free canvas) or a deck (slides). NOT for written documents: 'draft/write a doc, note, memo' is napkin_docs_create. Use when the user asks for one, or proactively when a sketch/deck would carry the conversation better than words; hand it over with `[[board:ID]]` alone on its own line. For a deck with content, prefer `napkin_deck_write` (one call, whole deck).

Returns a board's shapes as data — each with its id, kind, position, size, and text — so you can TARGET one to change or remove with napkin_draw (`updates` / `deletes` take these ids and absolute board coordinates). Pen strokes come back as a point count, not the points. For what the board LOOKS like, use napkin_boards_view instead. Board ids come from napkin_boards_list.

Lists sketch boards in the active workspace — name, id, kind (sketch / deck), shape count, last activity. Boards are SPATIAL canvases (drawing, diagrams); the markdown DOCUMENTS are docs — napkin_docs_list. Archived boards are hidden unless `includeArchived`; `q` narrows by name. When the user mentions a sketch, drawing, whiteboard, or napkin, find it here, then LOOK at it with `napkin_boards_view` before discussing its contents. When referring the user to a sketch in your reply, put `[[board:ID]]` alone on its own line — it renders as a clickable card with a live thumbnail.

Edits a board's details: name, description, visibility, or `archived` (true takes it out of the gallery; false brings it back — the recovery move for a board you created by mistake or the user no longer wants). Board ids come from napkin_boards_list. Boards are working material: no approval card, every change attributed.

Renders the sketch board to an image and returns it so you can SEE what's drawn — layout, arrows, handwriting-style strokes, sticky notes — not just data about it. Use this before answering any question about a sketch's contents, and cite the board when you do — `[[board:ID]]` alone on its own line embeds the sketch card in your reply.

Adds pictures to a brand kit section — logo versions, product marks, example screenshots, imagery. Each file comes from a public https `url` (fetched by the server) or, for a small file that isn't online, base64 `data` with a `filename`. PNG, JPEG, WebP, GIF and SVG, up to 20 MB each. Every file becomes a workspace file and an asset on the section, appended after the ones already there. Give each a `name` and a `note` saying what it's for; on logo sections set `backdrop` to the hex of the ground it's made for (#ffffff for a dark logo, #000000 for a reversed one), which is how pages pick the right version. Same rule as napkin_brand_draft: you can change any kit except the workspace's brand. Files that fail are reported and the rest still land.

Restyles a piece in the brand — the workspace's brand unless you name a kit. `deck` (a board id): every slide gets the brand's background, typefaces, and text colors; sizes are kept. `interface` (an interface id): rewrites its brand.css, so anything styled with var(--brand-*) updates. `accent` makes one of the kit's colors the piece's accent — use it when the piece is about one product or campaign that has its own color in the brand (read the kit's Colors section to see which). Docs need nothing — they read the brand when exported. Check a deck afterwards with napkin_slide_view.

Finds words the brand says to avoid in a piece of writing, with what to say instead and why. Pass `text`, or a deck (`boardId`) or doc (`docId`) to check its words. Run it on your own drafts before handing them back.

Creates a new brand kit, or edits one that is NOT the workspace's brand. Use it when someone asks you to put their brand together (from their site, a deck, or what they tell you) or to try a variation. You can't change the workspace's brand itself — make a draft and tell the user they can choose it in Napkin's Brand section. A kit is a document of sections, each with `title`, `kind` (overview, voice, colors, typography, logo, imagery, motion, layout, examples, custom), markdown `body`, and `rules` ({rule, why}); colors sections hold `swatches` ({name, value: 6-digit hex, note}), typography sections hold `faces` ({name: what it's for, family: a font name or sans / serif / mono / rounded / marker, note}), voice sections hold `use` and `avoid` ({term, instead, why}), and any section can hold `assets` ({fileId: an image already in the workspace's files, name, note, backdrop: hex}) — logo versions, example images — and `links` ({url, title, note}). An examples section holds work that gets the brand right: screenshots as assets and pages as links, each with a note on what makes it good. Exact numbers (timings, spacing) go in the section's prose. New kits start with empty standard sections plus the workspace's colors. `content.sections` upserts by title (or id): fields you pass replace, lists inside replace, sections you don't mention are kept; `removeSections` drops by title. `content.uses` says how Napkin uses the brand — color roles (ink, muted, background, surface, accent, accent2) and fonts (heading, body, mono) — by swatch or face NAME. Give every rule a `why`: the reason is what lets people decide cases the rule doesn't cover.

Shows you the pictures in a kit's Examples sections — screenshots of work that gets the brand right — with each one's note on what makes it good, plus the example links. Look before you design a deck, page or interface in the brand, and hold your work to the same bar: the layouts, density, type sizes and use of color you see there.

Gets the font files for a kit's typefaces from Google Fonts and keeps them in the kit, so decks, slide pictures and the canvas draw the brand's real typefaces instead of a stand-in. Only typefaces that name a family (like Poppins) and don't have files yet are fetched. Works on any kit, including the workspace's brand: it adds the files for the typefaces the kit already names and changes nothing else. A typeface Google doesn't have is reported back; the user can upload its files in the kit's typography section.

Reads a brand kit — the workspace's brand unless you name another. READ THIS BEFORE writing or designing anything for the workspace: a deck, a doc, an interface, copy. Returns `brief` (the whole kit as markdown: every section — overview, voice, colors, typography, imagery, motion, and whatever else the team wrote — with the reason behind each rule; follow the reasons when a case isn't covered), `css` (the `--brand-*` variables; interfaces already link it as brand.css, so style with var(--brand-accent) etc. rather than hex values), and `tokens` (the resolved values Napkin uses). Before any kit exists it returns values from the workspace's colors with `kit: null`.

Lists the workspace's brand kits: id, name, description, and which one is the workspace's brand (`isDefault`). Most workspaces have one. Use napkin_brand_get to read a kit.

Look at the pictures in a brand kit — logos, product marks, footage stills, layout references, examples — before you use them. Without `section` or `names` it lists every picture by section with its note, so you know what exists. With `section` (a section title, like Imagery) or `names` (pictures' names as the brief lists them) it shows you those pictures, up to 8 at a time. Look before you build a design around a picture: whether a photo has room for text, which part of it carries the color, and whether it suits texture inside type are things you can only tell by seeing it.

Builds a designed deck: each slide is a layout with its slots filled, or HTML and CSS you write; a real browser lays it out, and it becomes an ordinary Napkin deck people can edit. Use this whenever a deck should look designed — it's how to get layout, big numbers, color blocks, and pictures right. LAYOUTS FIRST - For ads, posts, carousels and title slides, start from a layout (napkin_layouts_list): give `layout` and `slots` instead of `html`. Layouts adapt to every size, fit their text, keep to each size's safe zones, and use the brand's own logos. A slide made from a layout remembers it, so when someone resizes it, it's laid out again instead of scaled. - A set of ads is one slide with `sizes`: ["1:1","4:5","9:16","1.91:1"] — each size gets its own arrangement. - Write HTML only for something no layout does. HOW TO WRITE A SLIDE - `html` is the inside of one slide: a `.slide` box 960×540 px (the deck's own size if it has one). Margins are reset; lay out with flexbox or grid, padding and gap. Put each slide's CSS in a <style> block inside its html, or shared CSS in `css`. - Read the brand first (napkin_brand_get). Style ONLY with its variables: var(--brand-ink), var(--brand-muted), var(--brand-background), var(--brand-surface), var(--brand-accent), var(--brand-accent-2), var(--brand-color-<color name>), var(--brand-font-heading), var(--brand-font-body), var(--brand-radius). Headings already use the heading face. - Pictures from the brand kit: <img src="kit:<file name exactly as the brief lists it>">, sized with CSS; object-fit: cover crops to fill, contain fits whole. Any workspace image: src="file:<file id>". - What carries over: boxes with a solid background, border, and rounded corners; text, including bold, italic, color, and size changes inside a line; pictures. What doesn't: gradients, shadows, background images, inline SVG — use solid color boxes instead. - Design like a designer: one idea per slide, a clear hierarchy, big numbers set large in the accent color, generous space, text 18px or larger (never under 14px), and something visual on most slides — a color panel, a photo, the logo. Keep every slide on the brand's own palette and voice. - Use the brand's own pictures. Put the logo on the title and closing slides (the reversed one on dark color), and use the kit's photos and icons where they carry the point — the brief lists every file under "Files", by name. - Say only what's true. Facts, figures, prices, eligibility, and how things work come from the brand kit and from what the user told you — never invent them. When a slide needs a fact you don't have, leave it out or ask. HOW TO USE IT - New deck: pass `name` and all `slides`. Rebuild a deck: pass `boardId` and all `slides` (replaces everything on it). - Ads, posts and other non-slide pieces: pass `size` — a key like `1:1` (square post, 1080×1080), `4:5` (portrait post), `9:16` (story or reel), `1.91:1` (LinkedIn or Facebook landscape), `og` (link preview), `300x250` or `728x90` (display ads). The `.slide` box is then that shape with its long side 960 px, so type sizes mean what they do on a slide, and the deck exports at the size's real pixels. A single ad is a one-slide deck; a carousel is a deck at `1:1` or `4:5`. - A set of ads — the same ad at several sizes, or several headlines — is one deck: give each slide its own `size`. Lay each size out for its own shape rather than squeezing one layout into all of them (a 9:16 story stacks what a 1.91:1 landscape puts side by side), and keep text out of the outer 7% of every edge and the top and bottom 14% of a 9:16. The deck's PNG export names each file by its pixels. Fix one slide: `boardId`, `slide` (1-based), and a single slide. Add slides: `append: true`. - The result lists each slide's `warnings` — text that overflows its box or the slide, overlapping text, text too small, low contrast, pictures that didn't load — and shows you a picture of every slide it made. Fix every warning and anything that reads badly in the pictures by recomposing just that slide. The contrast check is the standard one (4.5:1 for small text, 3:1 for large or bold text), so a contrast warning is real: darken the color, lighten the background, or set the text larger; never explain it away. You don't need napkin_slide_view afterwards: the pictures are the slides. - Cite the deck with [[board:ID]] alone on its own line.

Exports a deck's slides as PNG files at each slide's real pixels — a square post at 1080×1080, a story at 1080×1920, a leaderboard at 728×90 — ready to upload to an ad platform or a social post. One slide comes back as a PNG; several as a .zip named by deck, slide and size. Hidden slides are left out. The file is saved to the workspace's files; give the user `downloadUrl` (it opens for anyone signed in to the workspace) and say it's also in their files. Slide numbers and the workspace mark aren't drawn. For a PDF or PowerPoint, the user exports from the deck's File menu.

Returns a Napkin deck as a markdown outline — one section per slide in presentation order, with slide titles, text content (bold + bullets preserved), empty layout stubs still awaiting content, and a summary of drawn marks. This is the cheap way to know what a deck SAYS; use `napkin_slide_view` when you need to see how a specific slide LOOKS. Works on any board that has slides. Cite the deck with `[[board:ID]]` alone on its own line.

Paints every slide of a deck with a theme — slide background, heading and body typefaces, and text colors — in one call, the same as picking it in the deck's theme menu. Font sizes are kept. Prefer "brand" (the workspace's own brand kit) unless the user asks for something else. Built-in themes: plain (Helvetica on white. Gets out of the way.); editorial (Garamond headings on cream. Reads like a document.); stage (Helvetica, light on dark, for a projected room.); blueprint (Consolas headings on mist. For technical decks.); warm (Rounded on amber. Softer than it sounds.); notebook (Marker headings. Keeps the sketchbook feel.). For one-off colors or sizes on a single shape, use napkin_draw's `updates` instead. Check the result with napkin_slide_view.

Creates a deck from a markdown outline — the SAME dialect `napkin_deck_outline` reads back, so any deck you've read shows the format. Decks are SLIDES for presenting; a prose document ('write this up', 'draft a doc') is napkin_docs_create instead. Rules: `## Heading` starts a slide (heading becomes the slide title and its biggest text block); optional trailing `[layout: title | section | title-body | title-lead | two-column | three-column | comparison | statement | quote | closing | blank]`; body lines fill the layout's remaining text areas in order, split into areas by a line containing only `---`; `- ` bullets are kept as bullets. Slides default to title-body (or title, when bodyless). Layout text areas you don't fill stay as visible prompts for the user. Example: ## Q3 Review [layout: title] What happened, what's next ## Revenue [layout: title-body] - up 40% QoQ - churn flat ## Bets [layout: two-column] Double down on decks --- Sunset legacy plans After writing, cite the deck with `[[board:ID]]` alone on its own line — the user opens it from there.

Create a Napkin diagram — an interactive FLOWCHART (process, decision tree, system map), not a doc (napkin_docs_create) or drawing canvas (napkin_boards_create). Pass the mermaid source. Use for process maps the user asked you to draw. After creating, cite it as `[[diagram:ID]]` alone on its own line — it renders as a clickable card. NEVER cite it as [[board:ID]].

Fetch one Napkin diagram's mermaid source by id (from napkin_diagrams_list). Read before editing — napkin_diagrams_update replaces the whole source.

Lists the workspace's Napkin diagrams (interactive flowcharts — processes, decision trees, system maps) newest first. Archived diagrams are hidden unless `includeArchived`; `q` narrows by title. Fetch one's mermaid source with napkin_diagrams_get. When referring the user to a diagram in your reply, put `[[diagram:ID]]` alone on its own line — it renders as a clickable card. NEVER cite a diagram as [[board:ID]]; boards are sketches.

Edit a Napkin diagram: retitle, describe, REPLACE the whole mermaid source, set visibility, or `archived` (true takes it out of the gallery, false brings it back — the recovery move for a diagram created by mistake). Read the diagram first (napkin_diagrams_get) so your new source keeps the parts the user wants. Diagram ids come from napkin_diagrams_list.

Create a Napkin doc — a markdown DOCUMENT (prose, structure, code blocks), not a drawing canvas (that's napkin_boards_create) and not slides (napkin_deck_write). Optionally pass a title and initial markdown body. Use for drafts the user asked you to start. After creating, cite it as `[[doc:ID]]` alone on its own line — it renders as a clickable card. NEVER cite it as [[board:ID]].

Fetch one Napkin doc's full markdown body by id (from napkin_docs_list). Read before editing — napkin_docs_update replaces or appends against the current body.

Lists the workspace's Napkin docs (quick markdown documents — drafts, notes, working text; the LINEAR surface, distinct from boards which are drawing canvases) newest first, with excerpts. Archived docs are hidden unless `includeArchived`; `q` narrows by title. Fetch one with napkin_docs_get. When referring the user to a doc in your reply, put `[[doc:ID]]` alone on its own line — it renders as a clickable card. NEVER cite a doc as [[board:ID]]; boards are sketches.

Edit a Napkin doc. For a change to existing prose use `edits` — a list of exact find/replace pairs, which is the SAFEST option and the one to reach for by default: it leaves everything you did not target untouched, and it fails loudly rather than clobbering a doc somebody else is typing in. `append` adds a section at the end. `body` replaces the WHOLE document and should be a last resort. Also retitle, describe, set visibility, or `archived` (true takes it out of the gallery, false brings it back). Read the doc with napkin_docs_get first — `edits` match the current text exactly. Doc ids come from napkin_docs_list.

Draws shapes, strokes, and labels on a board — diagram on a sketch, annotate a deck slide — and, via `updates` / `deletes`, changes or removes shapes that are already there (ids from napkin_boards_get; the fix for something you drew wrong). For NEW elements never compute absolute board coordinates: with `slide`, coordinates are slide-local — (0, 0) top-left to (960, 540) bottom-right of that slide. Without `slide` (sketches), (0, 0) is the top-left of the existing content — the same area `napkin_boards_view` renders, so place by what you saw there; on an empty board just start at (0, 0). Example — circle a slide's title and margin-note it: {"boardId": "…", "slide": 2, "elements": [ {"type": "ellipse", "x": 60, "y": 40, "w": 400, "h": 90, "color": "#dc2626"}, {"type": "arrow", "x": 560, "y": 140, "x2": 470, "y2": 90, "color": "#dc2626"}, {"type": "text", "x": 575, "y": 130, "w": 260, "text": "tighten this claim", "color": "#dc2626"} ]} After drawing, cite the board with `[[board:ID]]` alone on its own line.

Create an interface — a small screen of its own the user can open and send to people. Use when someone asks for a custom chat UI, a little tool, or a prototype of how something would feel in their product. It starts with a working index.html you then edit. It can reach NOTHING in the workspace until a flow is granted with napkin_interfaces_grant. Cite it in your reply as `[[interface:ID]]` alone on its own line — it renders as a card the user can click. Do NOT paste an image URL or try to embed the picture yourself; that renders as a broken image. An interface is plain HTML, CSS and JavaScript in one or more files, served from its own origin. There is NO build step and NO library: no React, no Tailwind, no CDN. A <script src> to anywhere but this origin is blocked, so write vanilla JS and put styles in a <style> block. index.html is the entry point and must exist. THE BRAND: every interface carries the workspace brand as files — link it with <link rel="stylesheet" href="brand.css"> and style with its variables: var(--brand-ink), var(--brand-muted), var(--brand-background), var(--brand-surface), var(--brand-accent), var(--brand-accent-2), var(--brand-color-<colour name>), var(--brand-font-heading), var(--brand-font-body), var(--brand-radius). Never hard-code the brand's colours or font names. brand.css already loads the brand's own font files; web fonts (Google Fonts or any other) are BLOCKED, so linking one leaves the page in a system font. The brand's logos are files under brand/ (brand.css lists them at the top): <img src="brand/<name>.svg">. Use the logo rather than typing the name, and real icons (inline SVG) rather than emoji. Read the brand with napkin_brand_get first, and say only what the brand kit or the user tells you. PICTURES: a picture from anywhere on the web is BLOCKED and draws as a broken image, so never use an external image URL. Show a picture from the workspace's files with <img src="file:<fileId>" alt="…"> (in CSS, url(file:<fileId>)) — PNG, JPEG, GIF or WebP, up to 5 MB. Write the reference literally; a file id assembled in JavaScript is not found. When the user gives you a picture in chat, save it with workspace_files_save_from_chat and use the file id it returns. A picture that's only on a website has to be attached in chat first, or uploaded in the interface's Files panel. LOOK before you hand it over: napkin_interfaces_view draws the page as it is now. Fix anything that doesn't look like the brand and look again. Load the client with <script src="/zerowidth.js"></script>. Then zw.ready() resolves with { viewer, flows }, and zw.flows.run(flowId, input) runs a flow the interface was granted. Input is {kind:"chat", messages:[{role:"user", content:"…"}]} or {kind:"form", values:{…}} — the same shapes the public API takes. zw.replyText(result) pulls the assistant text out of a chat result. VARIABLES: a flow grant lists `variables` — the values the flow reads besides the conversation, usually the {{key}} tokens in its prompt (who the user is, their plan, the page they are on). Send them on the same chat run: {kind:"chat", messages:[…], values:{<name>: value}}, using each variable's exact `name` and its `type` (string, number, boolean, array, object). A variable left out reaches the prompt empty. Read them from napkin_interfaces_get while you write the page, or at run time from ctx.flows[i].variables. A SHIM is not a flow and takes a different call: zw.shims.run(shimId, text), which decides on the viewer's own device with no network and no cost. It resolves with the same envelope a flow does, so read the decision with zw.decision(result) — NOT result.decision, which is undefined and makes an interface show one answer for every input. The decision is { answer, confidence, familiarity, action, probs, gates }; branch on `action`, the shim's own call about whether it was sure enough. Calling zw.flows.run with a shim id is refused. ctx.grants tells you which you have: each entry carries a `kind` of "flow" or "shim" alongside its id and name. Running a shim on every keystroke is fine — it costs nothing and there is no rate limit. Debounce ~150ms and COALESCE: remember the latest text and run it when the current call finishes, so the answer matches what is on screen. Clear any in-flight guard on failure as well as success, or one call that doesn't come back wedges the interface. `d.action` is "act" | "suggest" | "refuse" — those three strings, nothing else. Branch on it rather than on a confidence threshold you invent; "refuse" means the shim doesn't recognise the input well enough to answer, so say so rather than showing a low-confidence guess. If you run a requestAnimationFrame loop, remove CSS transitions from any property it writes — the two fight and the property looks frozen. A flow answers in markdown: render it with el.replaceChildren(zw.markdown(text)). It builds DOM nodes, so model output is never treated as markup. STREAM chat answers: zw.flows.run(id, input, { onEvent: fn }) delivers the text token by token, and a flow that takes several seconds reads as broken without it. Use zw.textDelta(event) for each chunk — it returns null for anything that isn't text, so pass it every event — and accumulate. The promise still settles at the end with the whole result; take the final text from there. onEvent also sees node_start / node_complete / node_error if you want to name the step. Don't name a top-level variable `history`, `name`, `status`, `length`, `origin` or `top`: those are already window properties, so `var history = []` leaves you with the browser's History object and `history.push` fails. Prefix it, or keep it inside a function. Style it plainly and legibly: a system font stack, generous spacing, one column unless there's a reason. It runs on phones too.

Read one interface: its name, the flows it may run (with the published version each is pinned to), and the contents of its files. READ BEFORE EDITING — napkin_interfaces_write matches text exactly against what is there now. Pass a path to read one file when the interface has several. An interface is plain HTML, CSS and JavaScript in one or more files, served from its own origin. There is NO build step and NO library: no React, no Tailwind, no CDN. A <script src> to anywhere but this origin is blocked, so write vanilla JS and put styles in a <style> block. index.html is the entry point and must exist. THE BRAND: every interface carries the workspace brand as files — link it with <link rel="stylesheet" href="brand.css"> and style with its variables: var(--brand-ink), var(--brand-muted), var(--brand-background), var(--brand-surface), var(--brand-accent), var(--brand-accent-2), var(--brand-color-<colour name>), var(--brand-font-heading), var(--brand-font-body), var(--brand-radius). Never hard-code the brand's colours or font names. brand.css already loads the brand's own font files; web fonts (Google Fonts or any other) are BLOCKED, so linking one leaves the page in a system font. The brand's logos are files under brand/ (brand.css lists them at the top): <img src="brand/<name>.svg">. Use the logo rather than typing the name, and real icons (inline SVG) rather than emoji. Read the brand with napkin_brand_get first, and say only what the brand kit or the user tells you. PICTURES: a picture from anywhere on the web is BLOCKED and draws as a broken image, so never use an external image URL. Show a picture from the workspace's files with <img src="file:<fileId>" alt="…"> (in CSS, url(file:<fileId>)) — PNG, JPEG, GIF or WebP, up to 5 MB. Write the reference literally; a file id assembled in JavaScript is not found. When the user gives you a picture in chat, save it with workspace_files_save_from_chat and use the file id it returns. A picture that's only on a website has to be attached in chat first, or uploaded in the interface's Files panel. LOOK before you hand it over: napkin_interfaces_view draws the page as it is now. Fix anything that doesn't look like the brand and look again. Load the client with <script src="/zerowidth.js"></script>. Then zw.ready() resolves with { viewer, flows }, and zw.flows.run(flowId, input) runs a flow the interface was granted. Input is {kind:"chat", messages:[{role:"user", content:"…"}]} or {kind:"form", values:{…}} — the same shapes the public API takes. zw.replyText(result) pulls the assistant text out of a chat result. VARIABLES: a flow grant lists `variables` — the values the flow reads besides the conversation, usually the {{key}} tokens in its prompt (who the user is, their plan, the page they are on). Send them on the same chat run: {kind:"chat", messages:[…], values:{<name>: value}}, using each variable's exact `name` and its `type` (string, number, boolean, array, object). A variable left out reaches the prompt empty. Read them from napkin_interfaces_get while you write the page, or at run time from ctx.flows[i].variables. A SHIM is not a flow and takes a different call: zw.shims.run(shimId, text), which decides on the viewer's own device with no network and no cost. It resolves with the same envelope a flow does, so read the decision with zw.decision(result) — NOT result.decision, which is undefined and makes an interface show one answer for every input. The decision is { answer, confidence, familiarity, action, probs, gates }; branch on `action`, the shim's own call about whether it was sure enough. Calling zw.flows.run with a shim id is refused. ctx.grants tells you which you have: each entry carries a `kind` of "flow" or "shim" alongside its id and name. Running a shim on every keystroke is fine — it costs nothing and there is no rate limit. Debounce ~150ms and COALESCE: remember the latest text and run it when the current call finishes, so the answer matches what is on screen. Clear any in-flight guard on failure as well as success, or one call that doesn't come back wedges the interface. `d.action` is "act" | "suggest" | "refuse" — those three strings, nothing else. Branch on it rather than on a confidence threshold you invent; "refuse" means the shim doesn't recognise the input well enough to answer, so say so rather than showing a low-confidence guess. If you run a requestAnimationFrame loop, remove CSS transitions from any property it writes — the two fight and the property looks frozen. A flow answers in markdown: render it with el.replaceChildren(zw.markdown(text)). It builds DOM nodes, so model output is never treated as markup. STREAM chat answers: zw.flows.run(id, input, { onEvent: fn }) delivers the text token by token, and a flow that takes several seconds reads as broken without it. Use zw.textDelta(event) for each chunk — it returns null for anything that isn't text, so pass it every event — and accumulate. The promise still settles at the end with the whole result; take the final text from there. onEvent also sees node_start / node_complete / node_error if you want to name the step. Don't name a top-level variable `history`, `name`, `status`, `length`, `origin` or `top`: those are already window properties, so `var history = []` leaves you with the browser's History object and `history.push` fails. Prefix it, or keep it inside a function. Style it plainly and legibly: a system font stack, generous spacing, one column unless there's a reason. It runs on phones too.

Set what an interface may run — flows and shims, each pinned to a published version. This is the interface's ONLY reach into the workspace, and it replaces the whole list, so include everything it should keep. Ids and published versions come from workbench_flows_list / workbench_shim_list and their revisions. Ask the user before widening this.

List the interfaces in a workspace — small self-contained screens (a custom chat, a control panel, a prototype) that run on their own origin and can call the flows they've been granted. Returns ids, names and how many flows each may run.

Save where an interface is now as a numbered version. Share links point at a published version, so what someone was sent doesn't change while work continues. Do this when the user says it's ready to show people, not after every edit.

See what an interface LOOKS like right now: the whole page, drawn from its current files at desktop width under the same rules as the live page (no web fonts, no remote pictures). Use it after every write and before saying an interface is finished: reading the code tells you what you wrote, not what it renders. Look for text that's too small or runs together, stray system fonts, emoji standing in for icons, and anything that doesn't look like the brand.

Write one file of an interface. Use `edits` — exact find/replace pairs — which is the SAFEST option and the one to reach for by default: it leaves everything you did not target untouched, and it fails loudly rather than clobbering a file somebody is editing. `body` replaces the WHOLE file and is for a new file or a deliberate rewrite. `deleteFile` removes one (index.html can't be removed). Read with napkin_interfaces_get first — `edits` match the current text exactly. Also rename, describe, set visibility, or archive. An interface is plain HTML, CSS and JavaScript in one or more files, served from its own origin. There is NO build step and NO library: no React, no Tailwind, no CDN. A <script src> to anywhere but this origin is blocked, so write vanilla JS and put styles in a <style> block. index.html is the entry point and must exist. THE BRAND: every interface carries the workspace brand as files — link it with <link rel="stylesheet" href="brand.css"> and style with its variables: var(--brand-ink), var(--brand-muted), var(--brand-background), var(--brand-surface), var(--brand-accent), var(--brand-accent-2), var(--brand-color-<colour name>), var(--brand-font-heading), var(--brand-font-body), var(--brand-radius). Never hard-code the brand's colours or font names. brand.css already loads the brand's own font files; web fonts (Google Fonts or any other) are BLOCKED, so linking one leaves the page in a system font. The brand's logos are files under brand/ (brand.css lists them at the top): <img src="brand/<name>.svg">. Use the logo rather than typing the name, and real icons (inline SVG) rather than emoji. Read the brand with napkin_brand_get first, and say only what the brand kit or the user tells you. PICTURES: a picture from anywhere on the web is BLOCKED and draws as a broken image, so never use an external image URL. Show a picture from the workspace's files with <img src="file:<fileId>" alt="…"> (in CSS, url(file:<fileId>)) — PNG, JPEG, GIF or WebP, up to 5 MB. Write the reference literally; a file id assembled in JavaScript is not found. When the user gives you a picture in chat, save it with workspace_files_save_from_chat and use the file id it returns. A picture that's only on a website has to be attached in chat first, or uploaded in the interface's Files panel. LOOK before you hand it over: napkin_interfaces_view draws the page as it is now. Fix anything that doesn't look like the brand and look again. Load the client with <script src="/zerowidth.js"></script>. Then zw.ready() resolves with { viewer, flows }, and zw.flows.run(flowId, input) runs a flow the interface was granted. Input is {kind:"chat", messages:[{role:"user", content:"…"}]} or {kind:"form", values:{…}} — the same shapes the public API takes. zw.replyText(result) pulls the assistant text out of a chat result. VARIABLES: a flow grant lists `variables` — the values the flow reads besides the conversation, usually the {{key}} tokens in its prompt (who the user is, their plan, the page they are on). Send them on the same chat run: {kind:"chat", messages:[…], values:{<name>: value}}, using each variable's exact `name` and its `type` (string, number, boolean, array, object). A variable left out reaches the prompt empty. Read them from napkin_interfaces_get while you write the page, or at run time from ctx.flows[i].variables. A SHIM is not a flow and takes a different call: zw.shims.run(shimId, text), which decides on the viewer's own device with no network and no cost. It resolves with the same envelope a flow does, so read the decision with zw.decision(result) — NOT result.decision, which is undefined and makes an interface show one answer for every input. The decision is { answer, confidence, familiarity, action, probs, gates }; branch on `action`, the shim's own call about whether it was sure enough. Calling zw.flows.run with a shim id is refused. ctx.grants tells you which you have: each entry carries a `kind` of "flow" or "shim" alongside its id and name. Running a shim on every keystroke is fine — it costs nothing and there is no rate limit. Debounce ~150ms and COALESCE: remember the latest text and run it when the current call finishes, so the answer matches what is on screen. Clear any in-flight guard on failure as well as success, or one call that doesn't come back wedges the interface. `d.action` is "act" | "suggest" | "refuse" — those three strings, nothing else. Branch on it rather than on a confidence threshold you invent; "refuse" means the shim doesn't recognise the input well enough to answer, so say so rather than showing a low-confidence guess. If you run a requestAnimationFrame loop, remove CSS transitions from any property it writes — the two fight and the property looks frozen. A flow answers in markdown: render it with el.replaceChildren(zw.markdown(text)). It builds DOM nodes, so model output is never treated as markup. STREAM chat answers: zw.flows.run(id, input, { onEvent: fn }) delivers the text token by token, and a flow that takes several seconds reads as broken without it. Use zw.textDelta(event) for each chunk — it returns null for anything that isn't text, so pass it every event — and accumulate. The promise still settles at the end with the whole result; take the final text from there. onEvent also sees node_start / node_complete / node_error if you want to name the step. Don't name a top-level variable `history`, `name`, `status`, `length`, `origin` or `top`: those are already window properties, so `var history = []` leaves you with the browser's History object and `history.push` fails. Prefix it, or keep it inside a function. Style it plainly and legibly: a system font stack, generous spacing, one column unless there's a reason. It runs on phones too.

Lists the slide layouts napkin_deck_compose can build from — the brand kit's own first, then the built-in ones — with when to use each and the slots it takes (`needs` must be filled; `takes` are optional). Every layout adapts to every size, fits its text, and uses the brand's colors, faces and logos; the logo fills itself in. Pick by what the slide has to say: one line (statement), a number (stat), a quote, a list (points, steps), an event, a carousel (cover, inner, closing), a picture (image-top, image-full, split, corner, product-shot), or a display ad (banner).

Adds a LIVE chart to a sheet — its SQL re-runs against the tabs on every view, so it never goes stale. Write the query with napkin_sheets_query first to confirm the shape (first column = x axis, numeric columns = series, or set x/series explicitly). Prefer aggregated queries (GROUP BY) — a chart of raw rows is rarely the answer.

Creates a Napkin sheet (multi-tab spreadsheet), optionally titled. Then populate it with napkin_sheets_set_cells (headers in row 1). Tell the user where it landed — the Sheets tab in Napkin.

Lists the workspace's Napkin sheets (multi-tab spreadsheets — the small-data surface) newest first with tab/chart counts. Archived sheets are hidden unless `includeArchived`; `q` narrows by title. Inspect one with napkin_sheets_schema, then query it with napkin_sheets_query.

Runs a SQLite SELECT over a sheet's tabs-as-tables (get the table/column names from napkin_sheets_schema first). Full SQLite dialect: WHERE, GROUP BY, ORDER BY, JOINs across tabs, aggregates. Results cap at 200 rows. This is THE way to answer questions about a sheet's data — never eyeball cells when a query can answer precisely.

Returns a sheet's tabs as SQL table definitions — CREATE TABLE scripts with row counts (each tab is a table; its header row names the columns; formula cells contribute computed values). Read this BEFORE writing a napkin_sheets_query so your SQL matches the real tables.

Sets cells in one tab of a sheet, by A1 address — values or formulas ('=SUM(B2:B9)'). Additive and surgical: only the addressed cells change. Check napkin_sheets_schema first so you know the tab names and where data ends; put headers in row 1 when creating a new region. To build a whole small table, write header cells + data cells in one call.

Edits a sheet's details: title, description, visibility, or `archived` (true takes it out of the gallery; false brings it back — the recovery move for a sheet created by mistake or no longer wanted). Cells are edited with napkin_sheets_set_cells, not here. Sheet ids come from napkin_sheets_list.

Renders one of a sheet's pinned charts against the LIVE data and returns the image so you can SEE it — the exact chart the user sees. The text part carries `imageUrl`; to show the user the chart inline in your reply, put a markdown image on its own line: ``. Use after napkin_sheets_add_chart to confirm the chart reads well, or whenever the user asks about a chart.

Appends one slide to an existing deck. Pick a layout (title | section | title-body | title-lead | two-column | three-column | comparison | statement | quote | closing | blank), give the title, and optionally `content` — markdown for the layout's remaining text areas, split by `---` lines (two-column/comparison take one block per column). Check the deck first with `napkin_deck_outline`.

Fills a slide's empty layout text areas by NAME — the names `napkin_deck_outline` surfaces as `[empty text stub: "…"]`. Pass `texts` mapping those exact names to content (markdown `- ` bullets welcome). Read the outline first to see which stubs a slide still has open.

Changes one slide as a whole: move it to another position in the deck (`moveTo`, 1-based — the other slides shift around it), hide it from the show without deleting it (`skipped`), show or hide its slide number (`pageNumber`), or replace its speaker notes (`notes`, markdown). Slide numbers come from napkin_deck_outline. To change what's ON the slide, use napkin_slide_fill or napkin_draw.

Renders a single slide of a Napkin deck to an image — exactly what present mode shows, cropped to the slide. Navigate by 1-based `slide` number in presentation order (get the map from `napkin_deck_outline` first; the result echoes `slideIndex`/`slideCount` so you can step through a deck slide by slide). Use this to check visual layout, drawings, and images that the text outline can't carry.

Posts a comment on a workspace entity — a new thread, or a reply when rootId is given. Use it to leave findings where the discussion already lives (an eval result on the flow being debated, a summary on a long thread). Mention people via mentionedUserIds (from workspace member ids) to ring their notification bell; never mention someone who didn't ask to be pulled in.

Lists the comment threads on one workspace entity (open first, then resolved) with authors and timestamps. Read this before weighing in on contested work — the threads are where disagreement lives before it becomes a decision.

Sets a comment thread's resolved state (rootId = the thread's root comment id). Resolve ONLY when the human asked or the thread's question is demonstrably settled — and say what settled it in a reply first. Reopening is for new evidence.

Without a tag: every tag in use across the workspace with how many entities carry it, most-used first — the vocabulary the team already organizes by. With a tag: everything filed under it across every tool, each with its kind, id, title, and path. Use it to reuse existing labels instead of inventing near-duplicates, and to answer 'show me everything about X' when X is a label.

Returns the tags on a batch of entities of one kind — the labels galleries organize by. Ids come from the kind's list/get tool or from search_workspace. Use it before entity_tags_set so you replace the full set knowingly, and to answer 'what is this filed under'. Entities the user can't see are omitted.

Replaces the FULL tag set on one entity (an empty list clears it). Read the current tags with entity_tags_get first and pass the merged list — this is not additive. Tags are lowercase letters, numbers, spaces, and hyphens; prefer labels already in use (entity_tags_browse) so the workspace's vocabulary stays small. The id comes from the kind's list/get tool or search_workspace.

Enumerate all available docs pages, optionally filtered by product (e.g. 'compass', 'legal', 'overview'). Use this to discover what slugs exist before calling `get_doc`. No authentication required.

Search ZeroWidth product documentation. Returns matching pages with title, slug, public URL, and a query-relevant snippet. Use this when the user asks about a ZeroWidth product (Compass, Workbench, Caliper, Prism, Ledger, Napkin, zv1), an API behavior, or a policy. No authentication required — the docs corpus is public.

Finds entities across every tool by name in one call — Workbench flows, Compass pages, Caliper datasets, evals, rubrics, reviews, specs and sources (apps sending agent traces), Ledger entries, Napkin sketches and decks. Use it FIRST when the user names something without saying where it lives ('the onboarding flow', 'that invoice page'); reach for a tool's own list only when you already know the tool. Each hit carries its id, kind, and workspace-relative path, so the id feeds the matching *_get tool and the path makes a link. Results only include what the user can see, and only kinds this token may read.

Save a picture the user attached in THIS conversation to the workspace's files, in the Home folder "From chat", and get back its file id. Use it when the user wants a picture they sent you used somewhere — an interface shows it as <img src="file:<fileId>"> (CSS: url(file:<fileId>)). Pick the picture by `name`: the name in its `[attached image: <name>]` marker. Omit `name` only when the latest message with pictures has exactly one. Saving the same picture again returns the file it was already saved as. Only pictures from this conversation can be saved; a picture on a website can't be fetched, so ask the user to attach it here.

Fetch the full Markdown body of a specific docs page by its slug. Use this after `search_docs` when the user needs the complete content of a page. No authentication required.