Hollow

Hollow is a suite of fifteen apps that share one account, one shell and one assistant. This documentation covers every app, what Hollow AI can do inside it, and the behaviour that stays the same everywhere.

• Getting started: your first hour in the workspace.
• Hollow Studio: chat, Design Space, projects, media.
• App reference: every app, feature by feature.

Getting started

Sign in once and every app in the suite is open to you. There is nothing to install, no per-app setup and no second password.

1. Sign in. Email and password, with a reset link if you need one. You land on the Hub, your dashboard and launcher.
2. Open the app switcher. The switcher in the topbar lists every app grouped into Office Suite, Workspace Services and AI Workspace. Pick one; the shell stays put.
3. Press ⌘K. Search your work and run commands from anywhere in the suite.
4. Open the assistant. Every app has one. Ask it about what is on screen, or hand the job to Hollow Studio.
5. Make it yours. Choose a theme, an accent colour and an interface typeface in Appearance, then install the apps you use daily to your home screen or dock.

The workspace shell

Every app is built on the same frame, so nothing has to be relearned when you move between them.

Hub, your dashboard

Hub is where you land after signing in. It is the dashboard and launcher for the whole suite: your apps, your recent work, and a search box that answers rather than just listing.

• A home screen with the app switcher and your workspace at a glance.
• Search across the suite, with AI answers drawn from the web where that is what you asked for.
• A right rail with the assistant and quick actions.
• Account settings, sign-up and password reset.

Hollow Studio

Studio is the AI workspace: a conversation on the left, whatever the assistant is building on the right. It is where the long jobs happen: writing, designing, coding, generating media and working across your other apps.

Conversations

• Organise threads into folders, rename and search them.
• Fork a conversation to explore an alternative without losing the original, and branch individual messages.
• Attach files and images to a message; mention your projects, notes and objects with @.
• Set a system prompt per conversation, or standing instructions for a whole space.
• Save reusable prompts to a prompt library, share a conversation, or export it as Markdown.

Design Space

A live preview panel beside the thread. Static sites and React projects are bundled in the browser and rendered as you go, so you see the real thing rather than a code block. Point at an element to tell the assistant what to change, and share the space with someone else to review it together.

Artifacts

Anything the assistant produces becomes an editable object: code with a full editor, Markdown, documents, HTML previews, spreadsheets and SVG. Versions are kept, so you can step back.

Projects and code

Give Studio a project and it indexes the source so answers are grounded in your actual files. Connect a GitHub repository to sync it in, browse the tree, review staged changes, create branches, commit and open pull requests, all from the coding tabs in the dock.

Media

Generate images and video, and transcribe audio, inside the same session. The results land as artifacts alongside everything else.

Hey Hollow, voice

A live, spoken conversation with the same assistant and the same tools. Start a session from Studio, grant microphone access once, and talk.

• Listening and speaking states are always visible, with a running transcript of both sides.
• Interrupt at any time. Raise a hand mid-answer and it stops.
• Shown, not read. When an answer is a list, a table or a set of values, it is drawn on screen as a card instead of being recited.
• Confirm before writing. Any action that changes your data appears as a proposal with a plain-language summary, the app it touches and a risk level, and waits for your yes.
• Honest fallbacks for a denied microphone, an unsupported browser or an expired session. Never a silent failure.

The assistant in every app

Each app carries the same slide-in assistant in its dock. It already knows which app you are in and what you have open, so questions can be short.

• Same panel. Conversation history, model picker and streaming answers behave identically in all fifteen apps.
• Grounded. It reads the context you are in, whether that is the sheet, the board, the week or the thread, before it answers.
• Hands off cleanly. Anything bigger than a quick answer can be passed to Studio without retyping it.

Notes goes further with an inline editor assistant that works on the selection you have made, rather than in a side panel.

Tools and approvals

Hollow AI has a native toolset that reaches into your apps directly. Reads happen freely; writes are proposed and wait for you.

Beyond the built-in set, you can connect MCP servers to add your own tools, and set per-tool permissions so some actions run automatically while others always ask.

Models

Choose a model per message from the composer. Gemini 3.5 Flash is the everyday default; Gemini 3.1 Pro is the reasoning flagship.

• Chat and reasoning. Gemini 3.1 Pro, Gemini 3.5 Flash, Gemini 3.1 Flash Lite, Gemini 3.1 Deep Think, Claude Opus 4.8, Claude Sonnet 4.6, Claude Haiku 4.5, GPT-5.4 with mini and nano variants, Grok 4.3, Grok 4.1 Fast, Phi-4 mini and Phi-4 multimodal.
• Open models. Llama 4 Scout, Llama 4 Maverick, DeepSeek V3.2, Qwen 3 235B Instruct, Qwen 3 Coder 480B, Gemma 4 26B.
• Media and speech. Veo 3.1, Veo 3.1 Fast and Veo 3.1 Lite for video; Nano Banana 2 and Nano Banana Pro for images; Chirp 3 for speech.

Usage is metered per day against a budget you can see in settings, so a long session never becomes a surprise.

Skills, memory and agents

The assistant is configurable from one settings surface, shared across the suite.

• Skills. Reusable instructions you can invoke by name.
• Memory. Durable facts it should carry between conversations, all visible and deletable.
• Hooks. Rules that fire on events rather than on a prompt.
• Agents. Named configurations with their own model, tools and remit.
• MCP servers. Connect external toolsets, with recommended packs to start from.
• Permissions. Decide which tools run freely and which must ask.
• Writing style and AI preferences. Tone, defaults and per-app behaviour.

Tasks

Daily focus, structured properly. Tasks organises work into spaces and boards, gives you several ways to look at the same list, and can file incoming work for you.

Views

Home for today's focus, Inbox for anything unfiled, Lists for board work, Schedule for what is dated, saved Queries for your own slices, a Kanban per space, and Done for the archive.

Every task

Assignees, due dates and times, tags, subtasks, blockers, linked work in other apps, a rich description, and a detail panel with the lot. Reminders arrive through the bell in the topbar.

Intake

Publish an intake portal, define hooks and routing rules, and let requests land in a queue that files them to the right space with the right fields already set.

Alongside

A calendar block and a Pomodoro timer in the sidebar, share links for boards, auto-archive and auto-open preferences, and the assistant in the dock.

Create tasks from outside Hollow over the Tasks API →

Notes

Markdown notes that behave like a knowledge base. Notes is the polish benchmark for the whole suite, and everything else is built to match it.

Writing

A slash menu for blocks, a formatting toolbar, tables, highlights, images, checklists and a find bar. Version history is kept as you go.

Connecting

Wiki-links between notes, hashtags, a backlinks widget, tag filtering, and checklist items that resolve into real tasks.

Canvas

Each note can carry a canvas: a freeform surface with its own presence, comments and version history, available privately or synced with the people you share the notebook with.

Together

Share a notebook, edit at the same time with live presence and your own cursor colour, comment on a selection, and resolve edit conflicts from an inbox rather than losing work.

Rail

Backlinks, comments, tags, sharing, note activity, quick capture and a browser panel, plus the inline editor assistant that rewrites exactly what you have selected.

Workbooks

Spreadsheets with the parts that actually get used: a formula bar, multiple sheets, charts and the formatting rules that make a sheet readable.

• Formulas with a formula bar, named ranges and a live status bar.
• Charts through a wizard, rendered in the sheet.
• Conditional formatting and data validation rules.
• A format toolbar and sheet tabs for multi-sheet workbooks.
• Import and export dialogs for moving data in and out.
• A conflict banner when two people edit the same workbook, so nothing is silently overwritten.
• The assistant can read the sheet and set cells for you, on approval.

Slides

Presentations built from templates and layouts, with an outline view for structuring the argument before you style it.

• A template picker to start from, and a layout picker per slide.
• A slide canvas with rich text, a properties panel and an action bar.
• A thumbnail rail and an outline panel. Reorder from either.
• Present mode for delivery.
• A conflicts tab for collaborative edits.
• The assistant can draft a deck and add slides to an existing one.

Diagrams

Engineering maps you can draw or write. Diagrams live on a canvas with a properties panel, and the same diagram can be edited as code.

• A canvas with shapes, connectors and a properties panel for the selection.
• Diagrams as code: edit the diagram's definition as text and see it render.
• A collaboration tab with live cursors, and a conflict banner when edits collide.
• Diagram actions for duplicating, exporting and housekeeping.
• The assistant can create a diagram, update its contents and read one back to you.

Budgets

Personal and shared budgets, organised by period. Built around bills: what is due, what is paid, and who is covering it.

• A headline figure per period, with the bills listed beneath it.
• A bill drawer for the detail; mark paid inline.
• A sidebar tree for budgets and periods.
• Notes per period, so the context lives with the numbers.
• A People tab for shared budgets, with live cursors when someone else is in there with you.
• The assistant can add and update bills, set them paid, and answer questions about the period.

Contacts

The address book behind the suite. A searchable list, a detail drawer per person, and quick capture for someone new.

• A grouped, filterable contact list with a sidebar.
• A detail drawer for everything you hold about a person.
• Add a contact from anywhere in the app.
• Recipient fields elsewhere in the suite, such as Mail, autocomplete from here.
• The assistant can add, update and delete contacts, and answer questions across the book.

Cookbook

Meals and shopping. Keep recipes, plan the week, and cook from a screen designed to be read at arm's length.

• A recipe library you can search, plus your own recipes with a full editor and photos.
• A weekly plan: pick a day, pick a meal, build the menu.
• Cook mode: one step at a time, easy to follow while your hands are busy.
• Reminders through the bell, and live cursors when you plan with someone else.
• The assistant can search the library, draft steps for a recipe, generate a recipe photo and set the week's plan.

Files

The document hub for the suite. Folders, previews and a trash you can undo from.

• A folder hierarchy with a sidebar, toolbar and row list.
• A preview pane that renders the common formats in place.
• Drag-and-drop upload with a tray that tracks progress, including large files.
• Move, rename, trash and restore.
• The assistant can list your files, create folders, rename and move items, and trash or restore them on approval.

Yap

Spaces and channels for the conversations that should not be email.

• Spaces with a switcher, channels inside them and direct messages.
• Threads on any message, keeping the main channel readable.
• Reactions, an emoji picker, mentions and a mentions panel.
• Attachments, forwarding, message references and a search modal.
• Typing indicators, a members panel, and channel and space settings.
• The assistant can list your conversations and read messages back to you.

Mail

Webmail inside the workspace. Connect a mailbox and read it the way the rest of the suite reads, by conversation.

• Connect a mailbox and manage it from Mail settings.
• A folder sidebar, a message list and a conversation reader.
• Compose with recipient autocomplete drawn from Contacts.
• An outbox panel so you can see what is still sending.
• An attachments browser across your mail.
• Message bodies render in a sandboxed frame, so remote content cannot reach the rest of the app.
• The assistant reads the thread you have open and drafts from it.

Calendar

Four views of the same week, and a dock that tells you what is next.

• Day, week, month and agenda views with a current-time indicator.
• A mini calendar for jumping around, and a Today dock for what is imminent.
• An event modal with recurrence, and event types you can define and manage.
• Widgets and a right rail for the day's context.
• The assistant can list, create, update and delete events, and Tasks can show your calendar beside your work.

Cascade

Automation with no model in the execution path. A cascade is an ordered list of steps; each one runs an action and says what happens next on success and on failure.

Step types

• HTTP. Call an endpoint and thread the response into later steps, behind SSRF protection.
• Connector. The same call against a service you have connected once by OAuth, such as Slack, GitHub, Notion or Sheets. No pasted tokens: the credential lives server-side and never appears in the cascade.
• Hollow tool. Run any of the native suite actions as a step.
• Code. Write it in HollowScript, our own capability-safe language, or plain JavaScript or Python, run in an isolated sandbox with standard library only.
• Filter. A condition that decides whether the run carries on, branches or stops cleanly as a success.
• Loop. Repeat an inner action over a list from an earlier step, with a maximum-iterations guard.
• Delay. Wait, then continue. Short waits pause in place; long ones suspend the run and resume it durably.
• Approval. Hold the run until a person approves or rejects it, and route each outcome differently.

Control and triggers

Per-step retries and timeouts, jumps on success or failure, and guards against runaway loops. Run on demand, on a schedule, or from an inbound webhook.

Data and secrets

Every step declares typed outputs, and each later step shows what is available to it as clickable {{ steps.… }} references, so you can only point at data that exists. Credentials go in the secrets vault and are referenced as {{ secrets.NAME }}: the value is encrypted server-side, never stored in the cascade, never shown to the code sandbox, and masked out of every log and output preview.

Around the editor

A flow view of the whole cascade, a template gallery to start from, a runs view with per-step logs, a scheduled view, connections and secrets managers, and an alerts panel. Hollow AI can author and trigger cascades for you from Studio.

Lumen

Logs, metrics and alerts for everything the suite runs. Trace a request across apps, watch a Cascade run step by step, and set alerts that reach you wherever you already are.

Send logs, metrics and monitors over the Lumen API →

Sharing and collaboration

Sharing is per object and membership-based: you invite specific people, and access is enforced on the server rather than by an unguessable link.

• Share notebooks, task boards, budgets, diagrams and Design Spaces.
• Live presence and cursors wherever two people can be in the same thing at once.
• Comments anchored to a selection, with a comments panel per document.
• Version history on notes, canvases and artifacts.
• Conflict handling that surfaces the clash instead of quietly picking a winner.

Security and privacy

Hollow is built to keep your data yours: encrypted in transit and at rest, scoped to your account, and never used to train third-party models without you opting in.

• Encryption. TLS in transit everywhere, and data encrypted at rest.
• Authentication. Email-and-password sign-in behind a challenge and app-integrity check, with sessions you can review and revoke from Account settings.
• Access control. Sharing is membership-based and enforced on the server; nothing is reachable from an unguessable link.
• Isolation. Mail bodies render in a sandboxed frame, and Cascade's code steps run in an isolated sandbox with no reach beyond what a step explicitly calls.
• Your data, your call. Export your notes, files and conversations at any time; delete your account and the data goes with it.

Hollow is in early access; a full security whitepaper and compliance timeline will follow as the platform matures.

Appearance and accessibility

Set it once in Appearance and it follows you across every app.

• Two themes. Light and Dark.
• Custom accent. Pick a flat colour or a gradient; the whole suite picks it up.
• Interface typeface. Lexend by default, with Atkinson Hyperlegible and OpenDyslexic available.
• Keyboard first. ⌘K to search and run commands, ? for the full shortcut list.

Offline and installing

Every app is installable. Add it to your home screen or dock and it opens full-screen, with its own icon, like anything else you run.

Lose your connection and the topbar says so. You keep working; changes sync when you are back.

Account and access

• One email-and-password account covers the whole suite.
• Password reset by email, returning you to wherever you were headed.
• Account and security settings from the avatar menu in any app.
• Sign-in is protected by a challenge and app-integrity checks before your credentials are ever used.

Ready to start? Create an account and open the first app. Invite-only during early access. Get started

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