# Számlázz.hu MCP by usefulapi (remote · szamlazz-hu.usefulapi.io)

Read Számlázz.hu invoices, PDFs, receipts, taxpayers; issue, reverse and pay invoices and receipts.

- Trust score: 63/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-10-16

## Components

- remote · `szamlazz-hu.usefulapi.io`: 63/100 (this document), [markdown](https://verifymcp.io/servers/io-usefulapi-szamlazz-hu/szamlazz-hu.md), [page](https://verifymcp.io/servers/io-usefulapi-szamlazz-hu/szamlazz-hu)

## Channel facts

- Endpoint: `https://szamlazz-hu.usefulapi.io/mcp`
- Transports: `streamable-http`
- Auth: `required`
- Version: `1.0.0`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-10-16.

- **Endpoint Security**: 78/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation is enforced on tool calls, advertised via RFC 9728 protected-resource metadata. Discovery is public, which costs nothing: no tool can be invoked without a token.
  - HTTPS enforcement could not be verified: the plaintext port redirected somewhere other than https, so enforcement is unproven.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
  - The authorisation server offers only Dynamic Client Registration (RFC 7591), which MCP 2026-07-28 deprecated in favour of Client ID Metadata Documents.
- **Transport & Reachability**: 0/100
  - Transport check failed: declared streamable-http, but the endpoint redirected instead of responding directly.
- **Schema Quality & AI Usability**: 77/100
  - 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 2542 tokens (~231/item across 11 items; 11 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 13/100
  - Stability observed for 4 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - All 2 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation.
  - An AI judge read all 12 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 60/100
  - Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28.

## Install

### How do I install the Számlázz.hu MCP by usefulapi server?

Számlázz.hu MCP by usefulapi is a hosted endpoint at https://szamlazz-hu.usefulapi.io/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add --transport http io-usefulapi-szamlazz-hu 'https://szamlazz-hu.usefulapi.io/mcp'
```

### Cursor

```json
{
  "mcpServers": {
    "io-usefulapi-szamlazz-hu": {
      "url": "https://szamlazz-hu.usefulapi.io/mcp"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "io-usefulapi-szamlazz-hu": {
      "type": "http",
      "url": "https://szamlazz-hu.usefulapi.io/mcp"
    }
  }
}
```

### Codex

```toml
[mcp_servers.io-usefulapi-szamlazz-hu]
url = "https://szamlazz-hu.usefulapi.io/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "io-usefulapi-szamlazz-hu": {
      "type": "remote",
      "url": "https://szamlazz-hu.usefulapi.io/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add io-usefulapi-szamlazz-hu --url 'https://szamlazz-hu.usefulapi.io/mcp' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  io-usefulapi-szamlazz-hu:
    url: "https://szamlazz-hu.usefulapi.io/mcp"
```

### Netclaw

```json
{
  "McpServers": {
    "io-usefulapi-szamlazz-hu": {
      "Transport": "http",
      "Url": "https://szamlazz-hu.usefulapi.io/mcp"
    }
  }
}
```

### Vellum

```bash
assistant mcp add io-usefulapi-szamlazz-hu -t streamable-http -u 'https://szamlazz-hu.usefulapi.io/mcp'
```

### Other

```json
{
  "mcpServers": {
    "io-usefulapi-szamlazz-hu": {
      "type": "http",
      "url": "https://szamlazz-hu.usefulapi.io/mcp"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-10-15 (score 63, +1)

No change was recorded against any check on this day. Stability & Change Management went from 7 to 10. That category is still filling its 30-day observation window: 2 days of observed history at the previous scan, 3 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-13 (score 62, +3)

- [security] The server rewrote its instructions, which are the text every model session reads
- [functional improvement] Stability: unverified → 0.03
- [functional] The server now declares the “prompts” capability
- [functional] First check of Schema quality: 100
- [functional] New prompt “getting_started”
- [functional] Server version: 1.0.0 → 1.1.0

### 2026-10-12 (score 59)

First indexed and scored.

## MCP tools (11)

### `szamlazz_get_invoice` (~162 tokens)

Get an invoice

Read the data of one issued invoice (seller, buyer, lines, totals, VAT breakdown, payments) by invoice number, order number or your external id (give exactly one; for an order number with several invoices the last one is returned). Only invoices issued in this Számlázz.hu account. Also use it to check whether an invoice exists before issuing again. Számla Agent action-szamla_agent_xml.

Input parameters:

- `external_id` (string): The external id (szamlaKulsoAzon) given when the invoice was created.
- `invoice_number` (string): Invoice number, e.g. E-TST-2026-1.
- `order_number` (string): The order number given when the invoice was created.

### `szamlazz_get_invoice_pdf` (~119 tokens)

Get the PDF of an invoice

Download the PDF of one issued document (invoice, pro forma, ...) by invoice number, order number or your external id (give exactly one). Returns the totals and the PDF as an embedded resource. Számla Agent action-szamla_agent_pdf.

Input parameters:

- `external_id` (string): The external id given when the document was created.
- `invoice_number` (string): Invoice number, e.g. E-TST-2026-1.
- `order_number` (string): The order number given when the document was created.

### `szamlazz_check_taxpayer` (~101 tokens)

Check a Hungarian taxpayer

Look up a Hungarian taxpayer in the NAV register by the first 8 digits of the tax number (the törzsszám): whether the number is valid, the taxpayer's name, VAT status and addresses. Számla Agent action-szamla_agent_taxpayer (data from the NAV Online Invoice platform).

Input parameters:

- `tax_number` (string, required): The first 8 digits of the Hungarian tax number, e.g. 13421739.

### `szamlazz_get_receipt` (~93 tokens)

Get a receipt

Read one issued receipt (nyugta) by receipt number: lines, payments, totals, whether it was reversed. Optionally the PDF. Számla Agent action-szamla_agent_nyugta_get.

Input parameters:

- `pdf` (boolean): Also return the receipt PDF (default false).
- `receipt_number` (string, required): Receipt number, e.g. NYGTA-2026-1.

### `szamlazz_create_invoice` (~799 tokens)

Issue an invoice (fiscal, cannot be undone)

ISSUES a real invoice in Számlázz.hu. A final invoice is reported to NAV (Online Számla) and can only be cancelled by a reversal (szamlazz_reverse_invoice), never deleted. kind: invoice (default), proforma (díjbekérő; not fiscal, can be deleted with szamlazz_delete_proforma), prepayment (előlegszámla). The tool computes net, VAT and gross of every line from net_unit_price and vat_rate. preview true builds the PDF only and creates NO document (check the reply: a returned invoice_number means a document WAS created). This call is NEVER retried: if the result is unclear, look the invoice up (szamlazz_get_invoice by order_number or external_id) before issuing again; always send external_id or order_number so that you can. Setting send_email_to_buyer e-mails the PDF to the buyer. Számla Agent action-xmlagentxmlfile.

Input parameters:

- `buyer_address` (string, required): Buyer street address.
- `buyer_city` (string, required): Buyer city.
- `buyer_comment` (string): Note about the buyer.
- `buyer_country` (string): Buyer country name (default Magyarország).
- `buyer_email` (string): Buyer e-mail address.
- `buyer_eu_tax_number` (string): EU VAT number of the buyer.
- `buyer_name` (string, required): Buyer name.
- `buyer_phone` (string): Buyer phone.
- `buyer_postal_code` (string, required): Buyer postal code.
- `buyer_tax_number` (string): Hungarian tax number of a business buyer, e.g. 12345678-1-42. Not allowed on new-KATA accounts with protection on (error 491).
- `comment` (string): Comment printed on the invoice.
- `currency` (string): Currency code (default HUF). Not HUF: exchange_rate_bank and exchange_rate are required.
- `due_date` (string, required): Payment due date, yyyy-mm-dd.
- `e_invoice` (boolean): Issue an e-invoice (electronically signed). Default false; needs the e-invoice feature, else error 54.
- `email_body` (string): Text of that e-mail.
- `email_reply_to` (string): Reply-to address of that e-mail.
- `email_subject` (string): Subject of that e-mail.
- `exchange_rate` (number): Exchange rate, HUF per 1 unit of the currency (foreign currency only).
- `exchange_rate_bank` (string): Bank of the exchange rate, e.g. MNB (foreign currency only).
- `external_id` (string): Your own id for the invoice (szamlaKulsoAzon); lets you query it later.
- `fulfillment_date` (string, required): Date of delivery / service (teljesítés), yyyy-mm-dd.
- `issue_date` (string): Issue date, yyyy-mm-dd (default: today).
- `kind` (string): invoice (default), proforma (non-fiscal payment request) or prepayment (down-payment invoice).
- `language` (string): Language of the invoice (default hu).
- `lines` (array, required): Invoice lines.
- `order_number` (string): Order number; also usable to find the invoice later. The account may forbid repeating an order number.
- `paid` (boolean): Mark the invoice as already paid.
- `payment_method` (string, required): Payment method text, e.g. Átutalás (bank transfer), Készpénz (cash), Bankkártya (card).
- `prefix` (string): Invoice number prefix; must be registered in the account (Beállítások → Előtagok).
- `preview` (boolean): true = only return a preview PDF, create no document.
- `send_email_to_buyer` (boolean): E-mail the invoice to buyer_email (default false).

### `szamlazz_reverse_invoice` (~156 tokens)

Reverse (storno) an invoice (fiscal, cannot be undone)

ISSUES a reversal (storno) invoice that cancels one issued invoice. Fiscal: it is reported to NAV and cannot be undone; the original stays in the books. A reversal needs the invoice number of a real invoice. NEVER retried: if the result is unclear, check with szamlazz_get_invoice before trying again. Számla Agent action-szamla_agent_st.

Input parameters:

- `e_invoice` (boolean): Issue the reversal as an e-invoice (default false).
- `invoice_number` (string, required): Number of the invoice to reverse.
- `issue_date` (string): Issue date of the reversal, yyyy-mm-dd (default: today).
- `reason` (string): Reason, printed on the reversal.

### `szamlazz_delete_proforma` (~123 tokens)

Delete a pro forma invoice

DELETES one pro forma invoice (díjbekérő) by its number or by its order number (give exactly one). Only pro forma invoices can be deleted; a real invoice is never touched (use szamlazz_reverse_invoice). Cannot be undone. Számla Agent action-szamla_agent_dijbekero_torlese.

Input parameters:

- `invoice_number` (string): Number of the pro forma invoice, e.g. D-2026-12.
- `order_number` (string): Order number of the pro forma invoice.

### `szamlazz_register_payment` (~184 tokens)

Register payments on an invoice

Records 1-5 payments (kifizetés) on one of your own issued invoices or pro forma invoices, which updates its paid amount and outstanding balance. By default the payments are ADDED to the existing ones; replace_existing true REPLACES all earlier payment entries of the invoice. Not fiscal. Számla Agent action-szamla_agent_kifiz.

Input parameters:

- `currency` (string, required): REQUIRED: the invoice's currency (HUF, EUR, ...). Amounts are rounded to whole forints in HUF and to 2 decimals otherwise, so a wrong currency books a wrong amount.
- `invoice_number` (string, required): Number of your own issued invoice or pro forma invoice.
- `payments` (array, required): The payments (1 to 5).
- `replace_existing` (boolean): true = replace all earlier payment entries instead of adding (default false).

### `szamlazz_create_receipt` (~329 tokens)

Issue a receipt (fiscal, cannot be undone)

ISSUES a real HUF receipt (nyugta). Receipts are fiscal (NAV reporting) and can only be cancelled by szamlazz_reverse_receipt, never deleted. Give each line's whole-forint gross_total and vat_rate: the tool derives net, VAT and unit price (net + VAT equals gross exactly, as the vendor demands). The receipt prefix must be a receipt-only prefix (capital letters and digits, e.g. NYGTA), not an invoice prefix. call_id is required: the vendor refuses a second receipt with the same call_id (error 338), which protects against a duplicate. NEVER retried automatically: if the result is unclear, ask the user, then repeat the call with the SAME call_id (error 338 means the receipt already exists; find it in Számlázz.hu). Számla Agent action-szamla_agent_nyugta_create.

Input parameters:

- `call_id` (string, required): A unique id of this call (hivasAzonosito), new for every receipt: the vendor rejects a repeat, so the receipt cannot be issued twice.
- `comment` (string): Comment printed on the receipt.
- `lines` (array, required): Receipt lines.
- `order_number` (string): Order number printed on the receipt.
- `payment_method` (string, required): Payment method text, e.g. készpénz (cash), bankkártya (card).
- `prefix` (string, required): Receipt number prefix, capital letters and digits only, e.g. NYGTA. Must be a receipt-only prefix.

### `szamlazz_reverse_receipt` (~119 tokens)

Reverse (storno) a receipt (fiscal, cannot be undone)

ISSUES a reversal (storno) receipt that cancels one issued receipt. Fiscal and irreversible; a receipt can be reversed once, and a reversal receipt cannot be reversed. NEVER retried: if the result is unclear, check with szamlazz_get_receipt before trying again. Számla Agent action-szamla_agent_nyugta_storno.

Input parameters:

- `call_id` (string): A unique id of this call (hivasAzonosito).
- `receipt_number` (string, required): Number of the receipt to reverse.

### `szamlazz_send_receipt` (~126 tokens)

E-mail a receipt

E-MAILS an already issued receipt (PDF) to a customer. Without the e-mail fields, the vendor re-sends the receipt with the settings of the earlier e-mail. The e-mail cannot be recalled. Számla Agent action-szamla_agent_nyugta_send.

Input parameters:

- `body` (string): E-mail text.
- `email` (string): Recipient e-mail address.
- `receipt_number` (string, required): Number of the issued receipt.
- `reply_to` (string): Reply-to address.
- `subject` (string): E-mail subject.

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/io-usefulapi-szamlazz-hu/szamlazz-hu#diagnostics

## Score history

- 2026-10-16: 63
- 2026-10-15: 63
- 2026-10-14: 62
- 2026-10-13: 62
- 2026-10-12: 59

## Common questions

### What is the Számlázz.hu MCP by usefulapi server?

Számlázz.hu MCP by usefulapi is listed in the public MCP registry as io.usefulapi/szamlazz-hu. Read Számlázz.hu invoices, PDFs, receipts, taxpayers; issue, reverse and pay invoices and receipts. This page covers its hosted endpoint (https://szamlazz-hu.usefulapi.io/mcp).

### Is the Számlázz.hu MCP by usefulapi server safe to use?

Számlázz.hu MCP by usefulapi scores 63 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the Számlázz.hu MCP by usefulapi server expose?

Számlázz.hu MCP by usefulapi exposes 11 tools: szamlazz_get_invoice, szamlazz_get_invoice_pdf, szamlazz_check_taxpayer, szamlazz_get_receipt, szamlazz_create_invoice, and 6 more. Their descriptions and schemas cost roughly 2,311 tokens of context every time the server is loaded.

### Does the Számlázz.hu MCP by usefulapi server require authentication?

Yes. Számlázz.hu MCP by usefulapi asked us for credentials when we connected, so you will need to authorise it in your MCP client before it can do anything.

### Is the Számlázz.hu MCP by usefulapi server still maintained?

Számlázz.hu MCP by usefulapi is still listed as active in the MCP registry. We last reached this channel on 16 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

## Links

- Remote endpoint: https://szamlazz-hu.usefulapi.io/mcp
- Repository: https://github.com/m190/usefulapi-mcp
- Website: https://usefulapi.io/szamlazz-hu/
- Changelog RSS feed: https://verifymcp.io/servers/io-usefulapi-szamlazz-hu/szamlazz-hu.xml
- Changelog JSON feed: https://verifymcp.io/servers/io-usefulapi-szamlazz-hu/szamlazz-hu.json
- HTML version of this page: https://verifymcp.io/servers/io-usefulapi-szamlazz-hu/szamlazz-hu