How to Connect Fritz!Box Storage to Claude

Fritz!Box storage in Claude

Short answer: turn on FTP access and internet access to the storage on the Fritz!Box, and add it to AnythingMCP as a File Search connector over FTPS with the MyFRITZ address. AnythingMCP indexes the full text of the USB drive or NAS storage and keeps the index in sync. Then connect AnythingMCP to claude.ai, the Claude desktop app and Claude Code. Claude can find files by name and by content, read the pages it needs and give you the file itself, attached or as a temporary download link. Nothing is ever written to the Fritz!Box storage.

An AI assistant cannot open the storage of a Fritz!Box on its own, and one that could would have to download every file to answer one question. The index is what makes a question like "what does article NT-601 cost in the current price list?" take seconds.

What you need

• Access via FTP and Internet access to storage enabled on the Fritz!Box (Home Network → USB / Storage).
• The MyFRITZ address of the box and the FTP port it shows.
• A Fritz!Box user with access to the storage only.
• An AnythingMCP workspace: AnythingMCP Cloud (7 days free) or your own self-hosted install.

The Fritz!Box encrypts the connection with a self-signed certificate. That is fine: you confirm its fingerprint once in the wizard's test step, and AnythingMCP then refuses any other certificate.

Set it up

Step 1 — Set up the File Search connector

In AnythingMCP, open the Marketplace and pick Fritz!Box storage (File Search): it opens the File Search wizard with FTPS and the settings for the Fritz!Box. (Or open Connectors → New → File Search and use the Fritz!Box shortcut.)

1. Connect. Enter the MyFRITZ address, the FTP port the box shows, the Fritz!Box user and its password, and the folder on the storage to use.
2. Test. AnythingMCP connects, signs in and lists the folder before anything is saved, and shows a checklist (address, reachability, encryption, server identity, login, folder) with what to fix when a step fails. The Fritz!Box uses a self-signed certificate: the wizard shows its fingerprint, and you confirm it once. From then on AnythingMCP refuses a different certificate before the password is sent.
3. Scan. Click Scan folder. AnythingMCP lists the folder without indexing it yet and shows a tree with the number of files in every subfolder, the file types and the years. Folders that look like archives (Alt, Old, Archive, Backup) are already unticked, so Claude never quotes an outdated document. A bar compares your selection with your plan while you tick folders, file types or an age limit; when the selection is larger than the plan, untick more or upgrade.
4. Describe. AnythingMCP drafts the connector's description from the scan, for example "Office documents on the USB drive: invoices, offers and letters, PDF and Word, 2020–2026". This text tells Claude what the folder contains and when to search it. If an AI model is configured on the server, the wizard can draft it with AI and says exactly what is sent (folder names, file names, the first 2,000 characters of up to 20 sample files, personal data masked); otherwise the draft is built from the folder structure. Edit it as you like.
5. Activate. Choose the tool prefix, the sync interval and the MCP servers that get the connector, and click Activate.

The first sync starts right away and runs in a separate background service: Claude and your other connectors keep answering at full speed while it runs. The connector's Files tab shows its progress: files found, indexed and skipped, the last and next sync, and a Sync now button.

Step 2 — Copy the server URL

In MCP Servers, open the server you chose in the wizard and copy its URL.

Step 3 — Add the connector in Claude

Your server URL: in AnythingMCP, open MCP Servers → the server this connector is on, and copy its URL (https://cloud.anythingmcp.com/mcp/…). Use it wherever this guide shows YOUR_SERVER_ID.

Recommended path: works on claude.ai web without editing any config file.

1. In Claude, open Customize → Connectors.
2. Click +, then Add custom connector.
3. Enter a name, e.g. Fritz!Box storage, and the remote MCP server URL https://cloud.anythingmcp.com/mcp/YOUR_SERVER_ID, then click Add.
4. Click Connect and sign in to AnythingMCP (OAuth) to allow access.

The same connector appears in the Claude desktop app. In Claude Code: claude mcp add --transport http anythingmcp https://cloud.anythingmcp.com/mcp/YOUR_SERVER_ID --header "X-API-Key: <your MCP API key>".

Step 4 — Ask

Start a new chat and ask about the content of your files. Claude searches the index first, opens the pages that matched and answers with the file name, the page and the file's date, so you can check the source.

What Claude can do with the files

<prefix> is the tool prefix you choose in the wizard, for example pricelists. Every tool except _share_file only reads.

Supported files: text is extracted from over 100 file types: PDF (page by page); Word, Excel and PowerPoint including macro and template variants and .xlsb; OpenDocument; Outlook .msg, .eml and .mbox with the text of their attachments; .rtf, .epub, .xps; Apple Pages, Numbers and Keynote (through their PDF preview); .svg and the text of .dxf CAD drawings; CSV, Markdown, HTML, XML, JSON, YAML, calendars and contacts; and source code. Every other file is still found by name, and PDF pages and images can be shown to the AI as pictures. Scanned PDFs without a text layer are read with OCR on Enterprise.

Prompts to try in Claude

• "Find the invoice from Kessler for the heating repair and tell me the amount."
• "Which offers on the USB drive are from this year?"
• "Search the letters folder for anything about the lease of the office."
• "Give me the newest tax document as a download link."

How syncing works

AnythingMCP compares the size and modification time of every file with the last run and downloads only new and changed files. Files whose content is identical to the indexed version are recognised by their checksum (SHA-256) and not processed again. Deleted files leave the index. A file that cannot be read is retried on the next syncs and, after three failures (at once for password-protected files), stays findable by name, with the reason on the Files tab.

Syncing runs in its own background service, separate from the server that answers Claude: a large first sync does not slow down your questions, and search keeps working with the last index while a sync runs.

When the folder outgrows your plan, the sync pauses before downloading anything instead of indexing only part of it: the Files tab shows how many files the folder now holds against your plan, Claude keeps searching the files already indexed and is told that newer files may be missing, and you can untick folders or upgrade. A paused folder is checked again once a day and resumes by itself when it fits.

Security

• Read-only. The connector only lists and reads. It has no tool that writes, renames or deletes on the Fritz!Box storage.
• Your workspace only. The index is stored per workspace and every query is limited to it, by the application and again by the database (Row-Level Security).
• Credentials are stored encrypted and decrypted only in the background sync service. Claude and your colleagues never see them.
• Who sees what follows your MCP roles: a role without the file tools does not see them. On Enterprise you can also allow or deny folders per role.
• File content is data. The tools tell the model never to follow instructions found inside a file.
• Certificate pinned. The self-signed certificate you confirmed is checked on every connection, before the password is sent.
• A user for the storage only. The Fritz!Box user you give AnythingMCP should have access to the storage and nothing else, not to the box's settings.
• AnythingMCP Cloud connects only to servers on the public internet: a host in a private network is refused, also after a redirect. A server in your office network must be reachable from outside, or you run AnythingMCP self-hosted next to it.

Limits by plan

Self-hosted: Starter includes one File Search connector with up to 500 files, Team three connectors with 2,000 files, Enterprise has no limit and syncs down to every 5 minutes; the largest file is set by FILES_MAX_FILE_BYTES (100 MB by default). Self-hosted File Search needs a paid licence or the 30-day trial, which has the Team limits; the free Community edition has no File Search after the trial. All plans.

FAQ

Does it work on the Claude Free plan? Yes. Free plans can add one custom connector, and AnythingMCP counts as one no matter how many connectors you put on the server.

Why does the wizard ask me to confirm a fingerprint? The Fritz!Box uses a self-signed certificate, which no public authority vouches for. You confirm its fingerprint once; from then on AnythingMCP refuses any other certificate.

Which address do I enter? The MyFRITZ address of the box and the FTP port it shows. The storage must have internet access turned on, or AnythingMCP Cloud cannot reach it.

Does AnythingMCP copy all of the Fritz!Box storage? No. AnythingMCP keeps the extracted text, not the files. A file is read again only when it changed, or when you ask for the file itself.

Is vector search used? No. Company documents are searched for exact names, codes and numbers, where keyword search with page-level results is more reliable than embeddings.

Related

• Search your company file server with AI
• Find prices in supplier price lists with AI
• Search inside Nextcloud and WebDAV files with AI
• Share files from an AI chat as download links
• Connect Fritz!Box Storage to ChatGPT
• Connect Fritz!Box Storage to Gemini
• Connect Fritz!Box Storage to Microsoft Copilot
• Connect Fritz!Box Storage to Cursor
• Connect Fritz!Box Storage to Muse
• Other file sources in Claude: SFTP server, FTP / FTPS server, WebDAV server, S3 bucket, Nextcloud, ownCloud, Synology NAS, QNAP NAS, Hetzner Storage Box, Network folder (self-hosted)