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

Read-only probes

MCP server · Payments & trading

smallinvoice MCP by usefulapi

Read smallinvoice contacts, invoices, offers, projects and hours; create contacts and invoices.

Checks passed
14 / 22

0 failed · 8 not measured

Median response
59 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
27

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Outdated check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?
400
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 59 ms.

  • Pass
    Valid handshake

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

  • Pass
    Lists tools

    tools/list returned 27 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 59 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 59 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.

  • Pass
    Parameters documented

    130 of 130 parameters have a description (100%). 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 2026-11-10T23:34:19.387396Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using smallinvoice 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 smallinvoice-mcp-by-usefulapi https://smallinvoice.usefulapi.io/mcp

Capabilities

Tools 27

smallinvoice_create_contact

WRITE: creates a new company contact (customer) in smallinvoice, with its main address. Needs the "contact" scope. POST /contacts. Nothing is sent to anyone. Private persons are not supported here (smallinvoice needs more fields for them): create those in smallinvoice. Check smallinvoice_list_contacts first so you do not create a duplicate.

Discovered
smallinvoice_create_invoice

WRITE: creates a new invoice for a contact. Needs the "invoice" scope. POST /receivables/invoices. It is only created: it is NOT sent by e-mail or post and its status is not changed; the user reviews it in smallinvoice. Not idempotent: calling it twice creates two invoices. Use smallinvoice_list_contacts / smallinvoice_list_units first for the ids.

Discovered
smallinvoice_get_contact

One contact by id, with its fields. Add with=main_address for the main address. Needs the "contact" scope. GET /contacts/{id}.

Discovered
smallinvoice_get_delivery_note

One delivery note by id. Needs the "delivery_note" scope. GET /receivables/delivery-notes/{id}.

Discovered
smallinvoice_get_invoice

One invoice by id with its positions, totals and status. Needs the "invoice" scope. GET /receivables/invoices/{id}.

Discovered
smallinvoice_get_offer

One offer (quote) by id with its positions and totals. Needs the "offer" scope. GET /receivables/offers/{id}.

Discovered
smallinvoice_get_order_confirmation

One order confirmation by id. Needs the "order_confirmation" scope. GET /receivables/order-confirmations/{id}.

Discovered
smallinvoice_get_owner

The smallinvoice account the API client belongs to (the owner's id and details). A cheap check that the connection works. GET /auth/owner.

Discovered
smallinvoice_get_project

One project by id. Needs the "project" scope. GET /reporting/projects/{id}.

Discovered
smallinvoice_list_activities

List activities (the kinds of work that hours are booked on). Needs the "activity" scope. GET /reporting/activities. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_bank_accounts

List the account's bank accounts (as printed on documents). Needs the "configuration" scope. GET /configuration/bank-accounts. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_contact_addresses

All addresses of one contact. Needs the "contact" scope. GET /contacts/{contactId}/addresses.

Discovered
smallinvoice_list_contact_groups

List the contact groups. Needs the "contact" scope. GET /contacts/configuration/groups. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_contact_people

The contact persons of one company contact. Needs the "contact" scope. GET /contacts/{contactId}/people.

Discovered
smallinvoice_list_contacts

List contacts (customers and suppliers): name, type (company or person), relation, e-mail, currency. Add with=main_address for the address. Needs the "contact" scope. GET /contacts. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_cost_units

List cost units. Needs the "cost_unit" scope. GET /reporting/cost-units. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_delivery_notes

List delivery notes. Filter by contact_id or a JSON filter. Needs the "delivery_note" scope. GET /receivables/delivery-notes. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_efforts

List efforts (expenses and services recorded against projects). Needs the "effort" scope. GET /reporting/efforts. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_invoice_payments

The payments recorded on one invoice. Needs the "invoice" scope. GET /receivables/invoices/{invoiceId}/payments.

Discovered
smallinvoice_list_invoices

List invoices: number, contact, dates, total, currency, status. Filter by contact_id or a JSON filter. Needs the "invoice" scope. GET /receivables/invoices. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_offers

List offers (quotes). Filter by contact_id or a JSON filter. Needs the "offer" scope. GET /receivables/offers. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_order_confirmations

List order confirmations. Filter by contact_id or a JSON filter. Needs the "order_confirmation" scope. GET /receivables/order-confirmations. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_products

List the catalog's products (articles). Needs the "catalog" scope. GET /catalog/products. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_projects

List projects. Needs the "project" scope. GET /reporting/projects. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_services

List the catalog's services. Needs the "catalog" scope. GET /catalog/services. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_units

List the units (piece, hour, ...) with their ids, which an invoice position's unit_id refers to. Needs the "configuration" scope. GET /catalog/configuration/units. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered
smallinvoice_list_working_hours

List recorded working hours (time tracking entries). Needs the "working_hours" scope. GET /reporting/working-hours. Returns count, total, next_offset (pass it as offset for the next page) and the items.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected59 ms27