# Hippocampus FAQ

Hippocampus 0.91 (beta), October 2026. Screens and buttons are explained in the [User Guide](Hippocampus-User-Guide.md).

## Contents

- [Getting started](#getting-started)
- [Chat and answers](#chat-and-answers)
- [Wiki: summaries, pages and comments](#wiki-summaries-pages-and-comments)
- [Uploads (Import)](#uploads-import)
- [Search](#search)
- [Credits](#credits)
- [Plans, upgrade and downgrade](#plans-upgrade-and-downgrade)
- [Billing, payments and VAT](#billing-payments-and-vat)
- [Tenants](#tenants)
- [Adding users and sharing](#adding-users-and-sharing)
- [Connect to your AI](#connect-to-your-ai)
- [Security and privacy](#security-and-privacy)
- [Troubleshooting](#troubleshooting)

---

## Getting started

**What is Hippocampus?**
A knowledge base built from your own documents. Import files, then ask questions in plain language. Every answer cites the document, section and page it came from.

**How do I sign up?**
Go to hippo.thalius.ai and choose **Sign in with Google**, or enter your email and press **Email me a link**. Opening the link creates your account and your own tenant on Free.

**What do I get for free?**
Free gives you 1,000 credits every month, 1 user and 1 tenant, EU-hosted, with no card needed.

**What is my tenant's address?**
Each tenant has its own address, `<name>.hippo.thalius.ai`, suggested from your email when you sign up. Signing in on hippo.thalius.ai takes you there.

**Which sign-in methods are there?**
Google, an email link, or a password. To use a password, set one in **account menu → Set a password**, or use **Forgot password?** on the sign-in page.

**How long does a sign-in link work?**
Once, for 24 hours. Request a new one if it expired.

**What should I do first?**
1. **+ Import** a few documents into a folder.
2. Wait until the import shows **Done**.
3. Ask a question on Home, or pick a suggested question.

**Does it work on a phone?**
Yes, in the browser. **☰** opens the menu; originals open full screen.

---

## Chat and answers

**How do I ask a question?**
Type it in the box on Home, or in the ask box at the bottom of any folder or document page, and press Enter. **🎙** lets you speak it instead.

**How do I limit a question to one folder or document?**
Click the scope chip in the ask box (e.g. **Whole knowledge base**) and choose a folder. On a folder or document page the chip starts on that folder or document. A question about a document searches the folder that holds it.

**How do I check an answer?**
- Click a **Source p.N** chip to see the quoted passage.
- Click **Show original** to open the file at that page.
- Click **show reasoning** to see what was searched and which sections were used.

**What does the confidence bar mean?**
How well the found sources support the answer: High, Good, Moderate, Low or Very low. With Low or Very low, check the sources or narrow the question.

**Why does it say it can't find the answer?**
Hippocampus answers only from your documents. If they don't contain the answer, it says so instead of guessing. Check that the right documents are imported and finished, widen the scope, or rephrase.

**Can I ask follow-up questions?**
Yes. Keep typing in the same chat. **+ New question** starts a fresh chat.

**Can I stop an answer?**
Press **■** (Stop) or Esc. A stopped answer costs no credits for the answer; searches that already ran are charged. **Retry** asks again.

**Can it read answers aloud?**
Yes. **Listen** reads the answer; choose **Browser voice** or **OpenAI voice** in the input bar.

**Where are my old chats?**
In **History** (side menu) or **History** at the top of the chat. They are kept with your account, on every device.

**How do I delete a chat?**
**×** on the chat in History, then confirm. **History → ⋯ → Clear all history** deletes all of them.

**Which AI model writes the answers?**
The tenant's default answer model, set by the owner in **Settings → Profile**. The model name is shown under each answer.

**How do I give feedback on an answer?**
**Good answer** or **Bad answer** under the answer.

---

## Wiki: summaries, pages and comments

**What is the wiki?**
When you import a file, Hippocampus builds pages from it: a document summary, one page per section, a table of contents, folder summaries and a graph. They link together like a wiki you can browse.

**Does reading cost credits?**
No. Reading documents, summaries and sections is free on every plan.

**Can I write my own pages?**
Yes. In a folder, click **New document**, name it and press **Create and edit**. The editor has **Visual** and **Markdown** modes. Search finds the new text in under a minute; the summary refreshes in a few minutes.

**Can I edit an imported document?**
Not in the editor. Correct the file and import it again.

**How do I comment?**
Select text in a summary or section, click **Comment**, type and press **Comment**. Others can **Reply**; anyone who can comment can **Resolve**. You need edit rights on the document.

**Can I get the text out?**
Yes. **⋯ → Markdown** shows the full text as Markdown; **Show MD** at the page foot opens it in a new tab. The original file is always downloadable.

**What is the Graph view?**
A tree of folders, documents, sections, originals and comments. Click to unfold, double-click to open, scroll to zoom. **Show** chips choose what appears.

**How do I see a document's original?**
Click **Original** on the document, or the thumbnail. **↓** downloads it; **↗** opens it in a new tab.

---

## Uploads (Import)

**Which files can I import?**
PDF, Word (.docx), PowerPoint (.pptx), Excel (.xlsx), Markdown (.md, .markdown) and text (.txt, .text).

**How big can files be?**

| Limit | Value |
|---|---|
| Per file | 95 MB |
| Per import | 5,000 files |
| Folder depth | 32 levels |

**Can I import a whole folder?**
Yes. Drop it or use **Add file or folder → Choose folder**. Its structure is kept, as subfolders of the folder you save into.

**Does it read scanned PDFs?**
Yes. Scanned pages are read with OCR and cost more credits per page than text pages. **Advanced models** (Starter and Corporate) use stronger models for hard pages such as poor scans, tables and formulas.

**How much does an import cost?**
Credits per page, depending on the page type. See [Credits](#credits). The **Credits per page ↗** link in the dialog shows the current tariff.

**How long does it take?**
It depends on the number and kind of pages. The dialog shows each file's steps and time. You can close it; the side menu shows *Importing n/N*.

**Who can see what I import?**
Everyone with access to the folder you save into. **Who can see this?** in the Import dialog shows how many people that is before you import.

**Some files "couldn't be read". Why?**
Usually they are online-only files from OneDrive, Google Drive or Dropbox. Make them available offline (Windows: *Always keep on this device*; Mac: *Download Now*), then **Retry these files**.

**What happens if I import the same file twice?**
It is marked *Already imported* and skipped.

**How do I replace a document with a new version?**
Import the new file into the same folder. If someone edited the old text by hand, Hippocampus asks: **Import and replace** or **Skip this file**.

**Can I cancel an import?**
Yes. **Cancel import** stops files that haven't started. Files already being processed finish.

**How do I delete a document or folder?**
Document: **⋯ → Delete document**. Folder: the **Delete folder** icon in the folder, then type its name. Both are permanent.

---

## Search

**What is the difference between Search and Chat?**
Search lists the exact sections that match your words, with page numbers, and writes no answer. Chat writes an answer from the sections it finds, with citations.

**How do I search?**
Type in **Search documents** in the top bar (Ctrl K / ⌘K) and press Enter.

**Does search cost credits?**
Yes, a search costs credits like a question (see the tariff below). Opening the results is free.

---

## Credits

**What are credits?**
The unit Hippocampus charges in. One credit = €0.01.

**What costs credits?**

| Action | Credits |
|---|---|
| Import a text page | 1 |
| Import a scanned page | 2 |
| Import a page with tables, formulas or images | 3 |
| Import a page with Advanced models | 5 |
| Read documents, summaries, sections | 0 |
| Search | 2 |
| Question | 3 |
| Question with the premium answer model | 10 |

The current tariff is on **Plans → What each action costs ↗**.

**Where do I see my balance?**
The credits pill in the top bar. Hover it for the popup. Owners see usage per action in **Billing**.

**What do the pill colours mean?**
Green: under 50 % used. Yellow: from 50 %. Red: from 80 %.

**Who uses the credits?**
Credits belong to the tenant. Everyone in it draws from the same balance.

**When do credits renew?**
Every month on your renewal date, shown in the popup (*Credits reset on …*). Monthly credits reset; they don't carry over.

**What happens when credits run out?**
Questions, searches and imports pause; reading still works. Top up (Starter), upgrade (Free) or wait for the renewal date. A question you typed is kept.

**How do I buy more credits?**
Starter: **Top up** (Billing, Settings or the credits popup) → 1,000 credits for €10 → **Continue to payment**. Top-up credits never expire and are used after the month's credits. Free can't buy credits; upgrade first.

**Does each extra user bring credits?**
Yes. On Starter, each extra user adds 1,000 credits a month to the tenant.

---

## Plans, upgrade and downgrade

**What plans are there?**

| | Free | Starter | Corporate |
|---|---|---|---|
| Price (excl. VAT) | €0 | €30 a month or €250 a year | Custom |
| Credits every month | 1,000 | 3,000 | Custom |
| Users | 1 | €10 per extra user a month, +1,000 credits each | Custom |
| Tenants | 1 | 3 | Custom |
| Top-ups | — | €10 per 1,000 credits | Invoiced |
| Invite users, tenant administration | — | ✓ | ✓ |
| Advanced ingest models, premium answer model | — | ✓ | ✓ |
| Connect to your AI (MCP) | — | ✓ | ✓ |
| SSO, audit export, own DPA, own model key | — | — | ✓ |

**How do I upgrade?**
**Settings → Upgrade**, the credits popup, or **Plans → Upgrade**. Choose **Monthly** or **Yearly**, add users if you like, then **Continue to payment**.

**Do I lose anything when I upgrade?**
No. Same tenant, same documents, same links.

**When does the upgrade take effect?**
As soon as the payment is confirmed. The new credits are added then.

**How are extra users billed on a yearly plan?**
Monthly: €10 a month each, with 1,000 credits.

**How do I downgrade or cancel?**
**Billing → Change plan → Set downgrade for {date}**. The tenant moves to Free at the end of the paid period; nothing changes before then. **Keep Starter** undoes it until that date.

**What happens to my data when I downgrade?**
Nothing is deleted. Documents stay readable. Whatever is over Free's limits (e.g. extra users) waits for an upgrade.

**What is Corporate?**
A custom plan: credits, users and tenants sized to your needs, never locked at zero credits, SSO, audit export, its own DPA, your own model key, hosting to your requirements (EU) and dedicated support. Choose **Talk to us** on the Plans page.

---

## Billing, payments and VAT

**Who can see Billing?**
The tenant's owner.

**How do I pay?**
By card on a secure payment page (Stripe). It opens from **Continue to payment** and returns you to Hippocampus.

**Are prices with or without VAT?**
Without. Hippocampus also shows the amount with 25 % Swedish VAT, e.g. *Due today: 30 EUR excl. taxes (37.50 EUR with 25% VAT tax)*. The payment page calculates the VAT that applies to you.

**How do I add company details and a VAT number?**
**Billing → Billing settings**: fill in **Company details** and **Save company details**; enter the VAT number and **Check VAT** (checked in the EU VIES register). They appear on the next invoice.

**Where are my invoices?**
**Billing settings → Invoices → View**, then **Download PDF**.

**How do I change my card?**
**Billing settings → Card → Change card**.

**What if a payment fails?**
Hippocampus shows *Payment failed* and tries the card again. If the tenant is still unpaid after the grace period, only reading its documents works until it's paid. **Update card** fixes it. Your other tenants aren't affected.

**Why was I charged when I invited someone?**
When all paid users are taken, a new user is billed right away for the rest of the billing period. Their 1,000 credits arrive with that payment. From the next period the user is part of the monthly total.

---

## Tenants

**What is a tenant?**
A separate knowledge base with its own address, documents, members, credits and plan. People in one tenant can't see another tenant's documents.

**How many tenants can I have?**
Free: 1. Starter: up to 3. Corporate: custom.

**How do I create a new tenant?**
**Settings → New tenant** (or **Settings → Tenants → + New tenant**), enter a name, then pay. Each tenant is its own Starter subscription: €30 a month, 3,000 credits, billed on its own.

**How do I switch tenants?**
**Account menu → Tenant** → choose one. You continue, already signed in, at that tenant's address.

**How do I rename a tenant?**
**Settings → Profile → Name → Save**, or **Settings → Tenants → Rename…**.

**How do I delete a tenant?**
**Billing settings → Delete {tenant}…** and type its name. This deletes its documents and stops its subscription. Your first tenant can't be deleted; move it to Free with **Change plan**.

**Can I hand a tenant over to someone else?**
Yes. **Settings → Profile → Hand over ownership**. The new owner must already be a member. You stay a member.

---

## Adding users and sharing

**How do I add a user?**
Starter owners: **Settings → Members → Invite**, or **⋯ → Invite user** on All folders. Enter the email and press **Invite**. Free has one user only.

**What does the invited person get?**
An email with a link. If they have no account, one is created. After signing in they see *You've been invited* and press **Join**.

**What does a new user cost?**
€10 a month on Starter, with 1,000 extra credits a month for the tenant. If no paid user is free, the new one is billed now for the rest of the period.

**What is the difference between inviting and sharing?**
**Invite user** adds a person to the tenant. **Share** (on a subfolder or document) decides what a member can open (**Viewer**) or change (**Editor**).

**What can a Viewer and an Editor do?**
Viewer: read and ask. Editor: also import, write, rename, comment and delete in that folder or document.

**Does Share send an email?**
No. Tell the person yourself. If they're signed in, a page refresh shows the new folder.

**Can I share with someone outside my tenant?**
On Free and Starter, invite them to the tenant first, then share.

**How do I remove someone?**
**Settings → Members → Remove** (or **Revoke** for an open invitation). To take away access to one folder only: **⋯ → Share → ×** next to their name.

**Why can't a member see Settings?**
Settings is for owners and admins. Members read, ask, and import where they have edit rights.

---

## Connect to your AI

**What is it?**
A connector that lets Claude or ChatGPT search and read your Hippocampus documents over MCP, from inside the assistant.

**Which plans include it?**
Starter and Corporate.

**How do I connect?**
Open **Connect to your AI** in the side menu, copy the server address `https://hippo.thalius.ai/mcp`, and follow the steps for Claude, Claude Code or ChatGPT. Then sign in and approve in Hippocampus.

**What can the assistant see?**
Exactly what you can open, nothing more. It loses access when you do.

**How do I see what it looked up?**
**History → AI connector activity**. Only you see it; entries are kept for 90 days.

**How do I disconnect?**
**Connect to your AI → Connected apps → Disconnect**. Removing the connector only inside Claude or ChatGPT is not enough.

---

## Security and privacy

**Where is my data stored?**
In the EU on every plan. Corporate can choose hosting to its requirements.

**Who owns my documents?**
You do: documents, questions and the knowledge base built from them stay yours (Terms of service, "Your content").

**Is my data used to train AI models?**
No. The Data Processing Agreement says Thalius does not use customer personal data to train AI models and does not sell it.

**Who can see my documents?**
Only people with access to the folder or document, and AI apps you connected yourself (with your access). The **Share** dialog lists everyone with access.

**Are there legal documents?**
Yes: Terms of service and Privacy notice (links on the sign-in page), the Data Processing Agreement and the sub-processor list. Corporate can negotiate its own DPA.

---

## Troubleshooting

| Problem | What to do |
|---|---|
| No sign-in email | Wait a minute, check spam, then **Send it again** |
| *This sign-in link has expired or was already used* | Request a new link |
| Google window doesn't open | Allow pop-ups for hippo.thalius.ai |
| *Different tenant* page | You're signed in to another tenant. **Sign out and sign in here** |
| *No account exists for this address in this tenant* | Ask the tenant's owner to invite you |
| I can't find Settings | You're a member, not the owner |
| **Invite**, **New tenant** or **Advanced models** are grey | Your plan doesn't include them; hover for the reason and **See upgrade options** |
| Questions and imports are paused | Out of credits or payment due: **Top up**, **Upgrade** or **Update card** |
| *A new version is available* | Click **Refresh** |
| An answer stopped with an error | Click **Retry** |
| A file failed to import | Open the result list for the reason; online-only files need to be downloaded first |
| A folder I expect is missing | Ask the owner or an editor to share it with you |