4b2b MCP server for AI assistants
MCP (Model Context Protocol) lets an AI assistant call tools on a remote server. This server gives any compatible assistant direct, structured access to the public catalog of the 4b2b ecosystem, so it can answer with current data instead of guessing.
Endpoint and access
- URL
- https://4b2b.net/mcp
- Transport
- Streamable HTTP (JSON-RPC over POST), stateless
- Authentication
- None: no account, no key
- Access
- Read-only, public data only
- Rate limit
- 120 requests per minute per client
- Freshness
- Plans, prices and add-ons come from the live catalog (cached up to 10 minutes), the BNR rate up to 1 hour, markets up to 30 minutes, the answer index up to 6 hours
- Sources
- Every result carries source_url (the public page or feed it comes from) and as_of
The tools
| Tool | What it returns |
|---|---|
list_products | Every product of the ecosystem with its domain, what it is for and its group. |
find_product | The products that fit a need described in words, with the terms that matched (keyword matching, no AI). |
get_product | One product: definition, who it is for, key features, the countries and languages it is live in, its pricing page, llms.txt, llms-full.txt and sitemap. |
get_pricing | The current plans of one product in the market currency (EUR, USD on the dollar markets, plus a RON estimate for Romanian accounts): free period, price per billing period, yearly saving, limits, features and included services. |
get_options | The add-ons of one product: price, billing cycle, tiered or hourly prices and the plans each applies to. |
compare_plans | Two to eight plans side by side, with the same rows for each. |
estimate_cost | First invoice and renewal for a plan, a billing period and add-ons, with the checkout’s rules (free period, discounts). Excludes VAT. |
get_market_coverage | The products that are live in a country (ISO code, for example de), with the market page of each. |
list_site_templates | The 4buildsite website templates, with preview page and the plans that allow each. |
search_answers | Searches the published Q&A pages and guides of every site (laws, deadlines, definitions), in any language, and returns the short answer with its source and date. |
get_answer | One Q&A or guide page: its questions and short answers, date and link to the full text. |
calculate_vat | Net, VAT and gross from an amount and a rate you supply. It does not know any country’s rates. |
How to connect
In Claude Code, add it with one command:
claude mcp add --transport http 4b2b https://4b2b.net/mcpIn any other client that supports remote MCP servers, add a server of type Streamable HTTP with the URL below. No credentials are needed:
https://4b2b.net/mcpTo check it from a terminal, list the tools:
curl -s https://4b2b.net/mcp -H 'content-type: application/json' -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'What you can ask
Once connected, the assistant picks the right tool by itself. For example:
- What does 4invoices cost in the US? →
get_pricing - Which software do you have for a dental clinic? →
find_product - What would a VPS with a dedicated IP cost for a year? →
estimate_cost - Which 4b2b products are available in Germany? →
get_market_coverage - What registers must a Romanian PFA keep? →
search_answers - What is 1,000 net plus 21% VAT? →
calculate_vat
What it does not do
It cannot sign up, buy, create or change anything and has no access to customer accounts or data. It stores no tax rates: legal figures come only from the published answer pages, as of their date, and should be checked on the source page. Estimates exclude VAT and the checkout is authoritative. The fiscal calculators on the sites are not exposed through MCP.
Other machine-readable entry points
Assistants that read documents instead of calling tools can use:
/llms.txt— the index of every indexable page/llms-full.txt— the text of the pages as one markdown file (add ?market=<code> for another market)/sitemap.xml— the sitemap
Questions
What is an MCP server?
A server that exposes tools to AI assistants through the Model Context Protocol, an open standard. The assistant decides when to call a tool and shows you the result.
Do I need an account or an API key?
No. The server is public and read-only: no sign-in and no key.
Where does the data come from?
The product list comes from the ecosystem registry; plans, prices, add-ons and markets are read live from the same catalog that feeds the pricing pages and the checkout; answers come from the Q&A pages listed in each site’s sitemap.
In which currency are prices?
In EUR on every market, Romania included, and in USD in the United States, Puerto Rico, Ecuador, Panama, El Salvador and East Timor. A Romanian account pays in RON at the BNR rate of the day plus 5%; the server gives that as an estimate.
Can an assistant change anything through it?
No. Every tool only reads data.
