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Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Payments & trading

FastBill MCP by usefulapi

Read FastBill customers, invoices, estimates, expenses; create customers, invoices, projects.

Checks passed
13 / 22

1 failed · 8 not measured

Median response
66 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
22

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Outdated check

Last connection measurement is over 24 hours old. Current availability is unknown.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
310
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 66 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name fastbill-mcp.

  • Pass
    Lists tools

    tools/list returned 22 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 66 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 66 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Fail
    Parameters documented

    104 of 171 parameters have a description (61%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-11-10T23:34:20.994894Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using FastBill MCP by usefulapi

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http fastbill-mcp-by-usefulapi https://fastbill.usefulapi.io/mcp

Capabilities

Tools 22

fastbill_complete_invoice

WRITE, NOT REVERSIBLE: turn a draft invoice into a final invoice. FastBill assigns the invoice number and PDF; a final invoice can no longer be edited (it can only be canceled in FastBill). Nothing is sent to the customer. Only call this after the user confirmed the draft. invoice.complete.

Discovered
fastbill_create_article

WRITE: create a product or service (article number, title and unit price are required). article.create.

Discovered
fastbill_create_customer

WRITE: create a customer. customer_type is required; a business needs organization, a consumer needs last_name. Bank details are not accepted by this tool. FastBill does not check for duplicates, so search with fastbill_list_customers first. customer.create.

Discovered
fastbill_create_estimate

WRITE: create an estimate (quote) for a customer from line items. It is not sent. estimate.create.

Discovered
fastbill_create_invoice

WRITE: create an invoice for a customer from line items. FastBill stores it as a draft; it gets its number and becomes final only with fastbill_complete_invoice, and it is never sent by this tool. Check the result with fastbill_get_invoice. invoice.create.

Discovered
fastbill_create_project

WRITE: create a project for a customer (name and customer are required). project.create.

Discovered
fastbill_create_time_entry

WRITE: book a work time entry on a project (customer, project and start time are required). time.create.

Discovered
fastbill_get_customer

One customer by FastBill customer id. customer.get with CUSTOMER_ID.

Discovered
fastbill_get_invoice

One invoice by FastBill invoice id, with all line items, VAT, payments and the document URL. invoice.get with INVOICE_ID.

Discovered
fastbill_list_articles

List products and services (article number, type, title, unit price, VAT, unit). article.get.

Discovered
fastbill_list_contacts

List contact persons of customers (name, position, e-mail, phone). Filter by customer, search term or contact id. contact.get.

Discovered
fastbill_list_customers

List customers (name, address, e-mail, VAT id, payment terms and bank details as stored in FastBill). Filter by search term (organization, name, address, zip, e-mail or tags), customer number, country or city. customer.get.

Discovered
fastbill_list_estimates

List estimates (quotes) with state (a created, b sent, c negotiation, d accepted, e rejected, f invoiced), totals and items. estimate.get.

Discovered
fastbill_list_expenses

List expense entries (supplier, category, net/VAT/gross, dates, document URL). Filter by invoice number or date ranges. expense.get.

Discovered
fastbill_list_invoices

List outgoing invoices, drafts and credit notes with totals, state (draft, unpaid, overdue, paid, canceled), dates and line items. Filter by customer, number, type, date ranges (invoice date, due date, paid date, last update). invoice.get.

Discovered
fastbill_list_projects

List projects (name, customer, hourly rate, VAT, start/end date). project.get.

Discovered
fastbill_list_recurring_invoices

List recurring invoice templates (customer, interval data, totals, items). recurring.get.

Discovered
fastbill_list_revenues

List revenue entries (income booked in FastBill: customer, totals, dates, payments). Takes the same filters as invoices. revenue.get.

Discovered
fastbill_list_templates

List the invoice/estimate templates (template id, name, hash). Use a template id with the create tools. Ids change whenever a template is edited. template.get.

Discovered
fastbill_list_time_entries

List work time entries (customer, project, date, minutes, billable minutes, comment, invoice). Without filters FastBill returns the latest entries of the current month. time.get.

Discovered
fastbill_set_invoice_paid

WRITE: mark a final invoice as paid, with the payment date and method. invoice.setpaid.

Discovered
fastbill_update_customer

WRITE: update fields of an existing customer; only the fields you pass change. Bank details are not accepted by this tool. customer.update.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected66 ms22