Name: FastBill MCP by usefulapi
Author: usefulapi

FastBill MCP by usefulapi

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

Tool-list grade A Remote · Streamable HTTP No auth needed 22 tools v1.9.0 MIT

No reviews yet by usefulapiGitHub The publisher’s own endpoint — this marketplace is not in the path

93/100

tool-list score

tools declared

remote

at its publisher

—

calls last 7d

What it does

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

Quickstart

# 1 — add it to Claude Code
claude mcp add --scope user --transport http fastbill-mcp-by-usefulapi https://fastbill.usefulapi.io/mcp

# 2 — ask your agent for something these tools do
#   fastbill_list_customers, fastbill_get_customer, fastbill_list_contacts and 19 more

FastBill MCP by usefulapi costs nothing on mcprush: there is no plan to choose here, no cap to set and nothing mcprush can bill you for.

Publishernot claimed

usefulapi449 servers

24 categories

All 449 servers

Collected from a public index. Nobody has claimed this account, so nothing here was written by its author — claim it if it is yours.

Tool surface

What the model actually sees. Descriptions are diffed on every release — see version history.

Only tools that write or reach the network

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.

Parameter	Type	Required	Notes
term	string	no	Search term matched against organization, first/last name, address, zip code, e-mail and tags.
customer_number	string	no	Exact customer number.
country_code	string	no	ISO 3166 alpha-2 country code, e.g. DE.
city	string	no	—
limit	integer	no	Results per call, 1-100 (default 25). Every call counts against FastBill's hourly API quota.
offset	integer	no	Index of the first result, from 0 (default 0). Pass the previous reply's next_offset.

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

Parameter	Type	Required	Notes
customer_id	integer	yes	FastBill customer id.

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

Parameter	Type	Required	Notes
customer_id	integer	no	Only contacts of this customer id.
customer_number	string	no	—
term	string	no	Search term matched against organization, name, address, zip code, e-mail and tags.
contact_id	integer	no	One contact id.
limit	integer	no	Results per call, 1-100 (default 25). Every call counts against FastBill's hourly API quota.
offset	integer	no	Index of the first result, from 0 (default 0). Pass the previous reply's next_offset.

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.

Parameter	Type	Required	Notes
customer_id	integer	no	—
invoice_number	string	no	—
type	string	no	outgoing = finalized invoice, draft, credit = credit note.
start_date	string	no	Invoices dated on or after this day.
end_date	string	no	Invoices dated up to this day.
start_due_date	string	no	A date, yyyy-mm-dd.
end_due_date	string	no	A date, yyyy-mm-dd.
start_paid_date	string	no	A date, yyyy-mm-dd.
end_paid_date	string	no	A date, yyyy-mm-dd.
start_lastupdate	string	no	Changed on or after this day.
end_lastupdate	string	no	A date, yyyy-mm-dd.
limit	integer	no	Results per call, 1-100 (default 25). Every call counts against FastBill's hourly API quota.
offset	integer	no	Index of the first result, from 0 (default 0). Pass the previous reply's next_offset.

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

Parameter	Type	Required	Notes
invoice_id	integer	yes	FastBill invoice id.

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

Parameter	Type	Required	Notes
invoice_id	integer	no	One recurring invoice id.
limit	integer	no	Results per call, 1-100 (default 25). Every call counts against FastBill's hourly API quota.
offset	integer	no	Index of the first result, from 0 (default 0). Pass the previous reply's next_offset.

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

Parameter	Type	Required	Notes
customer_id	integer	no	—
estimate_id	integer	no	—
estimate_number	string	no	—
start_date	string	no	A date, yyyy-mm-dd.
end_date	string	no	A date, yyyy-mm-dd.
limit	integer	no	Results per call, 1-100 (default 25). Every call counts against FastBill's hourly API quota.
offset	integer	no	Index of the first result, from 0 (default 0). Pass the previous reply's next_offset.

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

Parameter	Type	Required	Notes
invoice_id	integer	no	—
invoice_number	string	no	—
start_date	string	no	A date, yyyy-mm-dd.
end_date	string	no	A date, yyyy-mm-dd.
start_paid_date	string	no	A date, yyyy-mm-dd.
end_paid_date	string	no	A date, yyyy-mm-dd.
limit	integer	no	Results per call, 1-100 (default 25). Every call counts against FastBill's hourly API quota.
offset	integer	no	Index of the first result, from 0 (default 0). Pass the previous reply's next_offset.

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

Parameter	Type	Required	Notes
customer_id	integer	no	—
invoice_number	string	no	—
start_date	string	no	A date, yyyy-mm-dd.
end_date	string	no	A date, yyyy-mm-dd.
start_paid_date	string	no	A date, yyyy-mm-dd.
end_paid_date	string	no	A date, yyyy-mm-dd.
limit	integer	no	Results per call, 1-100 (default 25). Every call counts against FastBill's hourly API quota.
offset	integer	no	Index of the first result, from 0 (default 0). Pass the previous reply's next_offset.

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

Parameter	Type	Required	Notes
article_id	integer	no	—
article_number	string	no	—
limit	integer	no	Results per call, 1-100 (default 25). Every call counts against FastBill's hourly API quota.
offset	integer	no	Index of the first result, from 0 (default 0). Pass the previous reply's next_offset.

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

Parameter	Type	Required	Notes
project_id	integer	no	—
customer_id	integer	no	—
limit	integer	no	Results per call, 1-100 (default 25). Every call counts against FastBill's hourly API quota.
offset	integer	no	Index of the first result, from 0 (default 0). Pass the previous reply's next_offset.

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.

Parameter	Type	Required	Notes
customer_id	integer	no	—
project_id	integer	no	—
time_id	integer	no	—
date	string	no	One day.
start_date	string	no	A date, yyyy-mm-dd.
end_date	string	no	A date, yyyy-mm-dd.
limit	integer	no	Results per call, 1-100 (default 25). Every call counts against FastBill's hourly API quota.
offset	integer	no	Index of the first result, from 0 (default 0). Pass the previous reply's next_offset.

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.

Parameter	Type	Required	Notes
limit	integer	no	Results per call, 1-100 (default 25). Every call counts against FastBill's hourly API quota.
offset	integer	no	Index of the first result, from 0 (default 0). Pass the previous reply's next_offset.

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.

Parameter	Type	Required	Notes
customer_type	string	yes	business or consumer.
organization	string	no	Company name (required for a business customer).
first_name	string	no	—
last_name	string	no	Required for a consumer.
salutation	string	no	—
position	string	no	—
academic_degree	string	no	—
address	string	no	—
address_2	string	no	—
zipcode	string	no	—
city	string	no	—
country_code	string	no	ISO 3166 alpha-2, e.g. DE.
email	string	no	—
phone	string	no	—
mobile	string	no	—
website	string	no	—
vat_id	string	no	VAT identification number.
currency_code	string	no	—
customer_number	string	no	Own customer number (FastBill assigns one if omitted).
days_for_payment	integer	no	Days until payment is due (stored with payment_type 1 only).

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

Parameter	Type	Required	Notes
customer_id	integer	yes	FastBill customer id.
customer_type	string	no	—
organization	string	no	Company name (required for a business customer).
first_name	string	no	—
last_name	string	no	Required for a consumer.
salutation	string	no	—
position	string	no	—
academic_degree	string	no	—
address	string	no	—
address_2	string	no	—
zipcode	string	no	—
city	string	no	—
country_code	string	no	ISO 3166 alpha-2, e.g. DE.
email	string	no	—
phone	string	no	—
mobile	string	no	—
website	string	no	—
vat_id	string	no	VAT identification number.
currency_code	string	no	—
customer_number	string	no	Own customer number (FastBill assigns one if omitted).

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.

Parameter	Type	Required	Notes
customer_id	integer	yes	FastBill customer id (see fastbill_list_customers).
items	array	yes	Line items (1-100).
currency_code	string	no	—
template_id	integer	no	Template id from fastbill_list_templates.
introtext	string	no	Introduction text above the items.
is_gross	boolean	no	True when unit_price values are gross.
discount_percent	number	no	Document discount in percent.
invoice_title	string	no	—
invoice_date	string	no	A date, yyyy-mm-dd.
delivery_date	string	no	A date, yyyy-mm-dd.
service_period_start	string	no	A date, yyyy-mm-dd.
service_period_end	string	no	A date, yyyy-mm-dd.
vat_case	string	no	VAT case (default standard).
cash_discount_percent	number	no	—
cash_discount_days	integer	no	—
customer_order_reference	string	no	—
contract_reference	string	no	—

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.

Parameter	Type	Required	Notes
invoice_id	integer	yes	FastBill id of the DRAFT invoice.

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

Parameter	Type	Required	Notes
invoice_id	integer	yes	FastBill invoice id.
paid_date	string	no	Date the payment arrived (default: FastBill's choice, today).
payment_method	string	no	e.g. paypal, cash, bank name.

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

Parameter	Type	Required	Notes
customer_id	integer	yes	FastBill customer id (see fastbill_list_customers).
items	array	yes	Line items (1-100).
currency_code	string	no	—
template_id	integer	no	Template id from fastbill_list_templates.
introtext	string	no	Introduction text above the items.
is_gross	boolean	no	True when unit_price values are gross.
discount_percent	number	no	Document discount in percent.
estimate_date	string	no	A date, yyyy-mm-dd.

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

Parameter	Type	Required	Notes
article_number	string	yes	Unique article number.
title	string	yes	—
unit_price	number	yes	—
type	string	no	—
description	string	no	—
unit	string	no	—
currency_code	string	no	—
vat_percent	number	no	—
is_gross	boolean	no	True when unit_price is gross.
tags	string	no	—

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

Parameter	Type	Required	Notes
project_name	string	yes	—
customer_id	integer	yes	FastBill customer id.
hour_price	number	no	Hourly rate.
currency_code	string	no	—
vat_percent	number	no	—
start_date	string	no	A date, yyyy-mm-dd.
end_date	string	no	A date, yyyy-mm-dd.

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

Parameter	Type	Required	Notes
customer_id	integer	yes	—
project_id	integer	yes	—
start_time	string	yes	Date and time, YYYY-MM-DD hh:mm:ss.
end_time	string	no	Date and time, YYYY-MM-DD hh:mm:ss.
minutes	integer	no	Duration in minutes (not calculated from the times).
billable_minutes	integer	no	—
article_id	integer	no	The service (article id) of the entry.
date	string	no	A date, yyyy-mm-dd.
comment	string	no	—

Free

$0 forever

Every tool — any call limit is its publisher’s, not ours
No card, and mcprush charges nothing for it
Runs at its publisher’s own address — this marketplace is not in the path
Nothing to cap, because mcprush bills nothing

Nothing here is billable: mcprush charges nothing to install FastBill MCP by usefulapi or to call it, at any volume.

ATool-list grade · score 93 / 100

Release 1.9.0 · scanned 1 Nov 2026

Graded from the tools this server lists, not from its source code.

Two independent axes, because powerful and malicious are different questions. The grade is threat only. The capability level is blast radius, and it is never a penalty on the grade — it is priced as one subtract-only term in the score, where you can see it.

Threat score100

Client score93

Findings0 threat · 1 capability

Capabilitymoderate

Coveragemanifest

Verificationnot in this report

Surface digesteed95a6eb9231bb88a1e787155f980e781353d36cddc582bcb20500adc914357

Score vectorthreat 100 → client 93

Term	Level	What it prices	Points
capability-exposure	moderate	capability blast radius (moderate) — client exposure if the model is manipulated	−3
coverage-honesty	manifest	inspection depth (manifest) — how much of the target the scan could see	−4

score = clamp(round(threatScore − E_cap − E_ver − E_cov), 0, 100). No model, no opinion, no network call at scoring time: the same methodology version against the same bytes always produces this number, and every line above is a field of the report rather than a summary of it.

What the scan could actually read

A grade is only as meaningful as its coverage, so the scanner publishes its own depth before it publishes its result.

The scan read each tool’s name, description, input schema and annotations exactly as the server listed them the last time it answered us; no code was reviewed. We ask the server again about once a month, and a list that changed is graded again.

Tool surfaceread

Implementation sourcenot available

Package metadatanot available

Live transportnot available

The implementation source was not read — this reflects the declared tool metadata only.

Capability — what it could do if the model were manipulated

Tags derived from each tool’s schema and the implementation, not from what the tool calls itself. moderate is the level these add up to.

Tool	Capability tags	Why the tag was assigned
fastbill_list_customers	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_get_customer	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_list_contacts	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_list_invoices	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_get_invoice	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_list_recurring_invoices	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_list_estimates	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_list_expenses	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_list_revenues	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_list_articles	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_list_projects	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_list_time_entries	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_list_templates	untrusted-input	untrusted-input: declares openWorldHint: true (interacts with entities outside the server)
fastbill_create_customer	external-sink	external-sink: declares readOnlyHint: false, openWorldHint: true
fastbill_update_customer	external-sink	external-sink: declares readOnlyHint: false, destructiveHint: true, openWorldHint: true
fastbill_create_invoice	external-sink	external-sink: declares readOnlyHint: false, openWorldHint: true
fastbill_complete_invoice	external-sink	external-sink: declares readOnlyHint: false, destructiveHint: true, openWorldHint: true
fastbill_set_invoice_paid	external-sink	external-sink: declares readOnlyHint: false, destructiveHint: true, openWorldHint: true
fastbill_create_estimate	external-sink	external-sink: declares readOnlyHint: false, openWorldHint: true
fastbill_create_article	external-sink	external-sink: declares readOnlyHint: false, openWorldHint: true
fastbill_create_project	external-sink	external-sink: declares readOnlyHint: false, openWorldHint: true
fastbill_create_time_entry	external-sink	external-sink: declares readOnlyHint: false, openWorldHint: true

Toxic-flow graph

The lethal trifecta, checked as a graph rather than as a checklist: untrusted input, a sensitive source and an external sink have to meet before there is a path worth worrying about.

flow-1

Untrusted input can drive an external action even though no sensitive source is exposed.

Supply chain and provenance

Integrityfirst-seen

Surface digesteed95a6eb9231bb8

Scanned2026-11-01

This is the first scan of this surface here, so there is nothing yet to compare it against.

Every result on this tab comes from one deterministic pass over the published package — offline, rule by rule, and auditable line by line above. Same methodology version, same bytes, same score.

Where are you running it?

Tool surface

Release history

FastBill MCP by usefulapi

What it does

Quickstart

Where are you running it?

Tool surface

What counts against your monthly calls

What the scan could actually read

Capability — what it could do if the model were manipulated

Toxic-flow graph

Supply chain and provenance

Release history

See also