filings.es MCP: the Spanish company register in your assistant

1. 1

   Download the installer file

   filings-es.mcpb3 Mo
2. 2

   Double-click the file

   Claude Desktop opens and shows the install window. If nothing happens, use Settings → Extensions → Install Extension, or drag the file onto the settings window.
3. 3

   Paste your key when Claude asks

   It stays on your machine: it never passes through this page.
4. 4

   Check it works

   In a conversation, ask “Who runs company B54226691?”. Claude should answer SOLER BULILLA SL.

1. 1

   Open Customize, then Connectors

   The free plan allows one connector; paid plans have no limit. On Team and Enterprise, only an owner can add them.
2. 2

   Click “+”, then “Add custom connector”

   Leave the advanced settings empty: this server does not use OAuth.
3. 3

   Paste this address, then “Add”

   https://api.filings.es/mcp?apikey=YOUR_KEY Copy
4. 4

   Enable it in the conversation

   This is the step people miss: an added connector is active in no conversation. Click the “+” at the lower left of the message box, then “Connectors”, and switch on filings-es.

1. 1

   Open a terminal

   Anywhere: “--scope user” below registers the server for all your projects. Without it, it would only be added to the current folder.
2. 2

   Run this command

   claude mcp add --transport http filings-es --scope user https://api.filings.es/mcp --header "X-Api-Key: YOUR_KEY" Copy
3. 3

   Check it works

   claude mcp get filings-es Copy

   The server should show as connected. The /mcp command, inside a session, lists the 19 tools.

1. 1

   Turn on developer mode

   Settings → Connectors → Advanced → Developer Mode. While it is off, no custom connector option appears — the number one cause of failed setups.
2. 2

   Click “Create”

   Name it filings-es and paste the address below as the server URL.

   https://api.filings.es/mcp?apikey=YOUR_KEY Copy
3. 3

   Tick “I trust this provider”, then “Create”

   The checkbox is required; the button stays disabled without it.
4. 4

   Enable it in every conversation

   Click “+” in the message box, then “More”, then “Developer Mode”, and select filings-es. Repeat in every new conversation.

To embed the register in your own product. No interface, no developer mode: the server is declared as a tool and the model decides when to call it.

1. 1

   Install the library

   pip install openai Copy
2. 2

   Declare the server and ask

   from openai import OpenAI client = OpenAI() resp = client.responses.create( model="gpt-5", tools=[{ "type": "mcp", "server_label": "filings_es", "server_url": "https://api.filings.es/mcp", "headers": {"X-Api-Key": "YOUR_KEY"}, "require_approval": "never", }], input="¿Quién administra la empresa con NIF B54226691?", ) print(resp.output_text) Copy
3. 3

   What you should get

   A plain-text answer citing SOLER BULILLA SL. To approve each call first, replace “never” with “always”. To restrict the model to certain tools, add “allowed_tools”.

1. 1

   Open the Connectors page

   Adding a connector is admin-only. On Free, Pro and Student plans, that is the account holder.
2. 2

   “+ Add Connector”, then the “Custom MCP Connector” tab

   For the name, write filings-es with no spaces or accents: the field rejects them.
3. 3

   Paste the BARE address, no key

   https://api.filings.es/mcp Copy

   Le Chat detects the authentication itself: click “Connect”, choose the Bearer token and paste your key in the form. Cleaner than a key in the URL.

4. 4

   Select it and test

   The connector appears in the tools dropdown. Ask “Who runs company B54226691?”: the answer should cite SOLER BULILLA SL.

1. 1

   Open the right file

   ~/.cursor/mcp.json for all your projects, or .cursor/mcp.json at a project root for that project only. Other editors read the same format.
2. 2

   Paste this configuration

   { "mcpServers": { "filings-es": { "url": "https://api.filings.es/mcp", "headers": { "X-Api-Key": "YOUR_KEY" } } } } Copy
3. 3

   Restart the editor

   Most only re-read their configuration on startup. In Cursor, the server is then enabled from Customize, in the sidebar.