Billy MCP by usefulapi
REMOTE · BILLY.USEFULAPI.IO
Read Billy invoices, bills, contacts, products and postings; create contacts and draft invoices.
Available components
Last scanned (1 hour ago)
Scores higher than 46% of remote servers
Reachable. Last reached 17 Oct 2026.
Category Finance and Payments
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. How we score → Why this is hard to score →
Endpoint Security78
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- 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. View diagnostics → Pass
- HTTPS enforcement could not be verified: the plaintext port redirected somewhere other than https, so enforcement is unproven. View diagnostics → Unverified
- HSTS check failed: the Strict-Transport-Security header is absent. See how to fix → View diagnostics → Fail
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
- The authorisation server offers only Dynamic Client Registration (RFC 7591), which MCP 2026-07-28 deprecated in favour of Client ID Metadata Documents. View diagnostics → Partial
Transport & Reachability0
- Transport check failed: declared streamable-http, but the endpoint redirected instead of responding directly. See how to fix → View diagnostics → Fail
Schema Quality & AI Usability79
- 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).Pass
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 2684 tokens (~178/item across 15 items; 15 tools + 0 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management17
- Stability observed for 5 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 15 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 16 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities60
- Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28. See how to fix → Fail
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 16 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 10 to 13. That category is still filling its 30-day observation window: 3 days of observed history at the previous scan, 4 at this one. The score rises as the window fills, whether or not the server changes.
- 14 Oct 26 +3
- The server rewrote its instructions, which are the text every model session reads security
- 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 functional
- 13 Oct 26 0
- Stability: unverified → 0.03 ▲ functional
- 12 Oct 26 60
First indexed and scored.
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 17 Oct 2026 · Probed https://billy.usefulapi.io/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=usefulapi.io | CN=WE1,O=Google Trust Services,C=US | 13 Sept 2026 | 12 Dec 2026 | ECDSA 256 | ECDSA-SHA256 | d9be3287b0fde9630e825ba1f79bff3f |
| SANs: usefulapi.io, *.usefulapi.io | ||||||
| CN=WE1,O=Google Trust Services,C=US (CA) | CN=GTS Root R4,O=Google Trust Services LLC,C=US | 13 Dec 2023 | 20 Feb 2029 | ECDSA 256 | ECDSA-SHA384 | 7ff31977972c224a76155d13b6d685e3 |
| CN=GTS Root R4,O=Google Trust Services LLC,C=US (CA) | CN=GlobalSign Root CA,OU=Root CA,O=GlobalSign nv-sa,C=BE | 15 Nov 2023 | 28 Jan 2028 | ECDSA 384 | SHA256-RSA | 7fe530bf331343bedd821610493d8a1b |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of billy.usefulapi.io. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| io. | present | 57355 | 8 | Verified |
| usefulapi.io. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication Enforced and verified
The endpoint asked for a token and published valid RFC 9728 metadata describing how to get one.
| Result | Enforced and verified |
|---|---|
| Enforced | On tool calls |
| HTTP status | 302 |
WWW-Authenticate challenge Bearer realm="OAuth", resource_metadata="https://billy.usefulapi.io/.well-known/oauth-protected-resource/mcp"
Bearer realm="OAuth", resource_metadata="https://billy.usefulapi.io/.well-known/oauth-protected-resource/mcp"Protected resource metadata
| Document | https://billy.usefulapi.io/.well-known/oauth-protected-resource/mcp |
|---|---|
| Retrieved | Yes |
| Resource | https://billy.usefulapi.io/mcp |
| Authorisation server | https://billy.usefulapi.io |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://billy.usefulapi.io/mcp | Redirected | 302 | https://usefulapi.io/billy/ |
| http (plaintext) | http://billy.usefulapi.io/mcp | Inconclusive | 302 | http://billy.usefulapi.io/mcp |
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
billy_create_contact Create a contact ~242
WRITE: create ONE new contact (customer and/or supplier) in the company's Billy account. It does not check for duplicates (call billy_list_contacts first) and nothing is sent to the contact. Not idempotent: a repeat call creates a second contact. POST /contacts.
| Name | Type | Req | Description |
|---|---|---|---|
| city | string | – | City. |
| contact_no | string | – | Your own customer or supplier number. |
| country_id | string | – | ISO country code (default DK). |
| ean | string | – | EAN location number for e-invoicing (Denmark). |
| string | – | Primary contact e-mail (stored as the primary contact person; nothing is sent). | |
| is_customer | boolean | – | Customer flag (default true). |
| is_supplier | boolean | – | Supplier flag (default false). |
| name | string | yes | Company or person name. |
| phone | string | – | Phone number. |
| registration_no | string | – | CVR number (Denmark) or EU VAT number. |
| street | string | – | Street and number. |
| type | string | – | company (default) or person. |
| zipcode | string | – | Postal code. |
No output schema declared.
No examples provided.
billy_create_draft_invoice Create a draft invoice ~215
WRITE: create ONE invoice in the DRAFT state for an existing contact. The invoice is NOT approved, booked, numbered into the ledger or sent: the user reviews it in Billy and approves and sends it there. The invoice number is assigned by Billy. No payment is created. Not idempotent: a repeat call creates a second draft. POST /invoices with state=draft.
| Name | Type | Req | Description |
|---|---|---|---|
| contact_id | string | yes | The customer's contact id (from billy_list_contacts or billy_create_contact). |
| contact_message | string | – | Message to the customer shown at the top of the invoice PDF. |
| currency_id | string | – | Invoice currency, e.g. DKK (default: the company's base currency). |
| entry_date | string | – | Invoice date yyyy-mm-dd (default today, UTC). |
| lines | array | yes | 1-100 invoice lines. |
| tax_mode | string | – | Whether unit prices include (incl) or exclude (excl) VAT (default: the company's setting). |
No output schema declared.
No examples provided.
billy_get_bill Get a bill ~43
One supplier bill by id with its lines. GET /bills/{id}.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | The bill id (from billy_list_bills). |
No output schema declared.
No examples provided.
billy_get_contact Get a contact ~48
One contact by id, with its contact persons (names and e-mail addresses). GET /contacts/{id}.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | The contact id (from billy_list_contacts). |
No output schema declared.
No examples provided.
billy_get_invoice Get an invoice ~60
One invoice by id with its lines (product, description, quantity, unit price, amount, tax) and its payment associations. GET /invoices/{id}.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | The invoice id (from billy_list_invoices). |
No output schema declared.
No examples provided.
billy_get_organization Get the company ~60
The Billy company the access token belongs to: id, name, address, registration (CVR) number, base currency, VAT settings, fiscal year, default payment terms, invoice numbering, default accounts. Good first call. GET /organization.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
billy_get_product Get a product ~43
One product by id with its unit prices per currency. GET /products/{id}.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | The product id (from billy_list_products). |
No output schema declared.
No examples provided.
billy_list_accounts List accounts (chart of accounts) ~129
The chart of accounts: account number, name, group, nature, VAT rate, bank-account flag and bank details (IBAN, bank name) of bank accounts. With is_bank_account=true this lists the bank accounts whose ids billy_list_bank_lines needs. Paged. GET /accounts.
| Name | Type | Req | Description |
|---|---|---|---|
| is_bank_account | boolean | – | true = only bank accounts. |
| page | integer | – | Page number, 1-based (default 1). Use next_page from the previous reply. |
| page_size | integer | – | Records per page, 1-200 (default 50). |
No output schema declared.
No examples provided.
billy_list_bank_lines List bank lines ~355
List the bank-statement lines of ONE bank account (read only; nothing is matched or reconciled): date, description, amount, side (debit/credit), reconciled flag, receipt state. Get the account id from billy_list_accounts with is_bank_account=true. Paged. GET /bankLines.
| Name | Type | Req | Description |
|---|---|---|---|
| account_id | string | yes | The bank account id (required). |
| entry_date_period | string | – | Date period: all, year:2026, month:2026-03, quarter:2026-2, dates:2026-01-01...2026-01-31 ... |
| is_reconciled | boolean | – | true = only reconciled lines, false = only unreconciled. |
| max_amount | number | – | Amount at most. |
| max_entry_date | string | – | Entry date on or before (yyyy-mm-dd). |
| min_amount | number | – | Amount at least. |
| min_entry_date | string | – | Entry date on or after (yyyy-mm-dd). |
| page | integer | – | Page number, 1-based (default 1). Use next_page from the previous reply. |
| page_size | integer | – | Records per page, 1-200 (default 50). |
| q | string | – | Free-text search over description or amount. |
| receipt_state | string | – | Only lines with a missing or uploaded receipt. |
| side | string | – | Only debit (money in) or credit (money out) lines. |
| sort_direction | string | – | Sort direction (default ASC). |
| sort_property | string | – | Sort by (default entryDate). |
| status | string | – | Line status (the API defaults to booked). |
No output schema declared.
No examples provided.
billy_list_bills List bills (supplier invoices) ~287
List bills (purchase invoices from suppliers): supplier, dates, state (draft/approved/voided), amount, balance, isPaid, supplier invoice number. Filter by state, supplier, dates or paid status. Paged. GET /bills.
| Name | Type | Req | Description |
|---|---|---|---|
| contact_id | string | – | Only bills of this supplier contact. |
| is_paid | boolean | – | true = only paid bills, false = only unpaid. |
| max_due_date | string | – | Due date on or before (yyyy-mm-dd). |
| max_entry_date | string | – | Bill date on or before (yyyy-mm-dd). |
| min_due_date | string | – | Due date on or after (yyyy-mm-dd). |
| min_entry_date | string | – | Bill date on or after (yyyy-mm-dd). |
| page | integer | – | Page number, 1-based (default 1). Use next_page from the previous reply. |
| page_size | integer | – | Records per page, 1-200 (default 50). |
| q | string | – | Free-text search over supplier name, description, voucher number, amount, supplier invoice number. |
| sort_direction | string | – | Sort direction (default ASC). |
| sort_property | string | – | Sort by (default entryDate). |
| state | string | – | Only bills in this state. |
| suppliers_invoice_no | string | – | Exact supplier invoice number. |
No output schema declared.
No examples provided.
billy_list_contacts List contacts ~156
List customers and suppliers: name, type, address, CVR/registration number, EAN, payment terms, customer/supplier flags. The API has no documented search filter, so `search` is applied to the returned page only (case-insensitive on name, contact number and registration number); page on with next_page to look further. Paged. GET /contacts.
| Name | Type | Req | Description |
|---|---|---|---|
| page | integer | – | Page number, 1-based (default 1). Use next_page from the previous reply. |
| page_size | integer | – | Records per page, 1-200 (default 50). |
| search | string | – | Keep only contacts on the returned page whose name, contactNo or registrationNo contains this text. |
No output schema declared.
No examples provided.
billy_list_invoices List invoices ~365
List sales invoices and credit notes (newest first by default): number, date, due date, state (draft/approved/voided), amount, tax, balance, isPaid, contactId, currency. Filter by state, customer, number, date, period, paid status or free text. Paged. GET /invoices.
| Name | Type | Req | Description |
|---|---|---|---|
| contact_id | string | – | Only invoices of this contact (from billy_list_contacts). |
| entry_date_period | string | – | Date period: all, year:2026, month:2026-03, quarter:2026-2, dates:2026-01-01...2026-01-31 ... |
| invoice_no | string | – | Exact invoice number. |
| is_paid | boolean | – | true = only paid invoices, false = only unpaid. |
| max_due_date | string | – | Due date on or before (yyyy-mm-dd); with is_paid=false this finds overdue invoices. |
| max_entry_date | string | – | Invoice date on or before (yyyy-mm-dd). |
| min_due_date | string | – | Due date on or after (yyyy-mm-dd). |
| min_entry_date | string | – | Invoice date on or after (yyyy-mm-dd). |
| page | integer | – | Page number, 1-based (default 1). Use next_page from the previous reply. |
| page_size | integer | – | Records per page, 1-200 (default 50). |
| q | string | – | Free-text search over invoice number, order number, contact name, line description, amount. |
| sort_direction | string | – | Sort direction (default ASC). |
| sort_property | string | – | Sort by (default entryDate). |
| state | string | – | Only invoices in this state. |
No output schema declared.
No examples provided.
billy_list_postings List ledger postings ~247
List ledger postings (the bookkeeping entries): date, text, account, amount, side (debit/credit), currency, voided flag. Filter by account, date or period. Read only. Paged. GET /postings.
| Name | Type | Req | Description |
|---|---|---|---|
| account_id | string | – | Only postings on this account (from billy_list_accounts). |
| entry_date_period | string | – | Date period: all, year:2026, month:2026-03, quarter:2026-2, dates:2026-01-01...2026-01-31 ... |
| is_voided | boolean | – | true = only voided postings, false = only live ones. |
| max_entry_date | string | – | Entry date on or before (yyyy-mm-dd). |
| min_entry_date | string | – | Entry date on or after (yyyy-mm-dd). |
| page | integer | – | Page number, 1-based (default 1). Use next_page from the previous reply. |
| page_size | integer | – | Records per page, 1-200 (default 50). |
| q | string | – | Free-text search over the posting text and the originator name. |
No output schema declared.
No examples provided.
billy_list_products List products ~131
List products and services usable as invoice lines: name, product number, description, sales account, archived flag. The API has no documented search filter, so `search` is applied to the returned page only (name, productNo). Paged. GET /products.
| Name | Type | Req | Description |
|---|---|---|---|
| page | integer | – | Page number, 1-based (default 1). Use next_page from the previous reply. |
| page_size | integer | – | Records per page, 1-200 (default 50). |
| search | string | – | Keep only products on the returned page whose name or productNo contains this text. |
No output schema declared.
No examples provided.
billy_list_tax_rates List tax (VAT) rates ~97
The company's VAT rates: name, rate (as a fraction, 0.25 = 25 percent), whether it applies to sales or purchases, active flag. Paged. GET /taxRates.
| Name | Type | Req | Description |
|---|---|---|---|
| page | integer | – | Page number, 1-based (default 1). Use next_page from the previous reply. |
| page_size | integer | – | Records per page, 1-200 (default 50). |
No output schema declared.
No examples provided.
How do I install the Billy MCP by usefulapi server?
Billy MCP by usefulapi is a hosted endpoint at https://billy.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.
remote · billy.usefulapi.io
claude mcp add --transport http io-usefulapi-billy 'https://billy.usefulapi.io/mcp'
What is the Billy MCP by usefulapi server?
Billy MCP by usefulapi is listed in the public MCP registry as io.usefulapi/billy. Read Billy invoices, bills, contacts, products and postings; create contacts and draft invoices. This page covers its hosted endpoint (https://billy.usefulapi.io/mcp).
Is the Billy MCP by usefulapi server safe to use?
Billy MCP by usefulapi scores 64 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 Billy MCP by usefulapi server expose?
Billy MCP by usefulapi exposes 15 tools: billy_get_organization, billy_list_contacts, billy_get_contact, billy_list_invoices, billy_get_invoice, and 10 more. Their descriptions and schemas cost roughly 2,478 tokens of context every time the server is loaded.
Does the Billy MCP by usefulapi server require authentication?
Yes. Billy 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 Billy MCP by usefulapi server still maintained?
Billy MCP by usefulapi is still listed as active in the MCP registry. We last reached this channel on 17 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.