MCP server

Filament Management includes a built-in MCP server, so an MCP client — Claude, or any other MCP-compatible tool — can read your inventory, or manage it, directly in conversation. There's nothing extra to install or host: turn it on in Settings, point your client at one URL, and sign in with your normal account.

Enabling it

Under Settings → MCP server (admin only):

• Enable MCP server — off by default. While off, the server rejects every request, including ones from clients that connected before it was disabled.
• Access mode — Read-only exposes list/get tools only. Read and write additionally exposes create/update/delete tools. Switching modes takes effect immediately for every already-connected client, not just new connections — there's no separate token to reissue or revoke, and no other way to grant write access short of this toggle.

The page also shows the server URL you'll give to your MCP client:

https://your-instance/api/v1/mcp

Everything else — where to authenticate, how to register as a client — is discovered automatically by the client from that one URL, per the MCP authorization spec.

Connecting from Claude

Claude.ai (web or desktop)

1. Open Settings → Connectors in Claude.
2. Choose Add custom connector.
3. Paste your server URL (https://your-instance/api/v1/mcp) and confirm.
4. Claude opens a browser window to your Filament Management instance. Log in if you're not already, then approve the consent screen — it names the connector and the access level it's requesting (matching whatever mode is currently set in Settings).
5. Once approved, the connector shows as connected and its tools (list_spools, create_spool, etc.) are available in chat.

Any other MCP client that supports a remote, OAuth-authenticated server over Streamable HTTP can connect the same way — point it at the same URL and follow its own login prompt.

What's actually happening

Filament Management acts as its own OAuth 2.1 authorization server for this: the client registers itself automatically (no manual client ID/secret to create), then redirects your browser through a normal login (or your workspace's SSO provider, if configured) followed by a one-time consent screen. The client never sees your password — it only ever receives a scoped access token after you explicitly approve it. Tokens expire after an hour and refresh automatically in the background for as long as the connector stays added; nothing needs re-approving unless you remove and re-add it.

Available tools

Every tool operates only on your own workspace's data — there's no way for a connected client to see or affect another tenant, regardless of what it's told.

Read-only (always available once enabled)

Tool	Description
list_spools	List spools, with optional filters by vendor, material, color, remaining weight, storage location, stored/unstored, archive status, or free-text search, sorted by ID, remaining weight, or opening date
get_spool	Get one spool by ID
list_filaments	List filament types
get_filament	Get one filament type by ID
list_vendors	List vendors
get_vendor	Get one vendor by ID
list_storage_locations	List storage locations and their slot counts
get_storage_location	Get a storage location with all of its slots and their occupying spools
list_free_storage_slots	List empty storage slots, optionally in one location
get_inventory_summary	The same overview as the dashboard: totals, remaining and used weight and value, fill levels, low-stock spools, and breakdowns by material and vendor
get_spool_weight_history	A spool's weight history, plus how much filament it used over that period
calculate_print_cost	Price a print from the filament used, print time, and an optional handling fee, using your cost settings

Read and write (only when Access mode is set to "Read and write")

Tool	Description
create_spool / update_spool / delete_spool	Manage spools
create_filament / update_filament / delete_filament	Manage filament types
create_vendor / update_vendor / delete_vendor	Manage vendors
create_storage_location / update_storage_location / delete_storage_location	Manage storage locations
create_storage_slots / update_storage_slot / delete_storage_slot	Add, rename, or remove slots in a storage location
share_print_cost	Price a print like calculate_print_cost and return a public link to the result (see Sharing a calculation)
consume_filament	Subtract the filament a print used from a spool
set_spool_weight	Record a weighing — either the filament weight, or the raw scale reading with the empty spool subtracted automatically

Weight changes made over MCP behave like the ones made in the app: they're added to the spool's weight history, mark the spool as opened on first use, and refresh any e-paper display showing that spool. Delete tools are marked as destructive, so clients like Claude ask before running them.

Things to try

• "I just printed a 42 g benchy with the red PLA, log it."
• "Which spools are running low, and what's the remaining PLA worth?"
• "Find a black PETG spool with at least 300 g left and tell me where it's stored."
• "How much would a 120 g print in the grey PLA that takes 5 hours cost?"
• "Price 80 g of the orange PLA plus a 3 € fee for 'Keychains' and give me a link I can send."
• "Add slots A1 to A12 to the Shelf location."

If a client calls a write tool while the workspace is in read-only mode (or tries any tool while the server is disabled), it gets a clear error back instead of silently failing — this is checked on every single call, not just at connection time.

Revoking access

There's currently no per-client list to revoke individually. To cut off MCP access:

• Turn off "Enable MCP server" in Settings — every connected client, including ones with an active token, is rejected immediately.
• Switch to "Read-only" — keeps read access working but immediately removes write access from every connected client.

To remove a specific connector's own record of the connection, remove it from that client's side (e.g. Claude's Connectors settings) — it will simply be prompted to reconnect and re-approve if added back later.