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io.usefulapi/numeral

REMOTE · NUMERAL.USEFULAPI.IO · SCANNED AUG 3

Calculate sales tax & VAT, record transactions and refunds, manage products and customers.

−50 this week 18 Trust /100
Trust breakdown (6 categories)

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 →

Endpoint Security46
Transport & Reachability0
Schema Quality & AI Usability0
  • Schema not yet verified: we couldn't read the endpoint's schema.Unverified
Stability & Change Management0
  • Stability not yet verified: not enough scan history yet (needs a 30-day window).Unverified
Tool Coverage0
  • Tool coverage not yet verified: we couldn't read the endpoint's tools.Unverified
Capabilities0
  • Capabilities not yet verified: we couldn't read the endpoint's capabilities.Unverified

Unverified: 4 categories

Categories scored 0 because we could not verify them: authentication we do not have, an unreachable endpoint, or not enough scan history. We only credit what we can confirm.

Install

Add this component to your MCP client. Where a client-specific snippet is available, pick your client below and copy it straight into your config; otherwise use the connection detail shown.

remote · numeral.usefulapi.io

# add to Claude Code
claude mcp add --transport http io-usefulapi-numeral https://numeral.usefulapi.io/mcp
# ~/.codex/config.toml
[mcp_servers.io-usefulapi-numeral]
url = "https://numeral.usefulapi.io/mcp"
// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "io-usefulapi-numeral": {
      "type": "remote",
      "url": "https://numeral.usefulapi.io/mcp",
      "enabled": true
    }
  }
}
# add to OpenClaw
openclaw mcp add io-usefulapi-numeral --url https://numeral.usefulapi.io/mcp --transport streamable-http
# ~/.hermes/config.yaml
mcp_servers:
  io-usefulapi-numeral:
    url: "https://numeral.usefulapi.io/mcp"
// mcp.json
{
  "mcpServers": {
    "io-usefulapi-numeral": {
      "type": "http",
      "url": "https://numeral.usefulapi.io/mcp"
    }
  }
}

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

Changelog

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.

  • 1 Aug 26 −53
    • Endpoint reachability: reachable → not serving MCP security
    • Stability: 0.13 → unverified security
    • Authorization: pass → unverified security
    • Transport: pass → fail security
    • Capabilities: fail → unverified functional
    • Tool coverage: 100 → unverified functional
  • 31 Jul 26 +3
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 30 Jul 26 −2
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 29 Jul 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.

  • 28 Jul 26 +1
    • Stability: unverified → 0.03 functional
  • 27 Jul 26 +56
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 26 Jul 26 12

    First indexed and scored.

Diagnostics

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 3 Aug 2026 · Probed https://numeral.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 19 Jul 2026 17 Oct 2026 ECDSA 256 ECDSA-SHA256 f3886899c43cacbe13984ee09ea259a5
SANs: usefulapi.io, numeral.usefulapi.io, *.numeral.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
DNSSEC insecure

Validation of numeral.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 No authorisation required

The endpoint answered without asking for a token. Anyone who knows the URL can reach it.

Result No authorisation required
HTTP status 429
Header Value
x-frame-options SAMEORIGIN
referrer-policy same-origin
Transports 2 probes
Transport URL Outcome Status Location
streamable-http https://numeral.usefulapi.io/mcp HTTP error 429
http (plaintext) http://numeral.usefulapi.io/mcp Inconclusive 429
MCP tools — 11 exposed · ~1,113 tokens

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.

Tool Tokens
numeral_calculate_tax ~170

Calculate sales tax / VAT for an order — a STATELESS quote that persists nothing (record it later with numeral_create_transaction using the returned calculation id). Returns per-jurisdiction rates, total_tax_amount, and totals. Provide a customer address and one or more line items (each needs reference_product_id OR product_category). Amounts are in the currency's smallest unit (cents). Numeral: POST /tax/calculations.

NameTypeReqDescription
customerobjectyesCustomer details — address is required.
metadataobjectArbitrary string key/value metadata.
order_detailsobjectyesOrder details.
origin_addressobjectThe address a product ships from. Optional on 2024-09-01; required on API version 2025-05-12+.

No output schema declared.

No examples provided.

numeral_create_customer ~99

CREATES a customer record — this WRITES to your Numeral customer list (used for order tracking and tax exemptions). Numeral: POST /tax/customers.

NameTypeReqDescription
emailstringyesCustomer email (required).
is_tax_exemptbooleanWhether this customer is tax exempt.
namestringCustomer name.
reference_customer_idstringYour own id for this customer (for reference-based lookups).

No output schema declared.

No examples provided.

numeral_create_product ~112

CREATES (or upserts) a product with its tax category — this WRITES to your Numeral product catalog, which drives future tax calculations. Numeral: POST /tax/products.

NameTypeReqDescription
product_categorystringyesA tax category from Numeral's taxonomy, e.g. "GENERAL_MERCHANDISE", "SAAS_GENERAL".
reference_product_idstringyesYour product id (used to reference this product in calculations).
reference_product_namestringyesHuman-readable product name.

No output schema declared.

No examples provided.

numeral_create_refund ~155

RECORDS a refund against a transaction — this WRITES a live tax/compliance record (adjusts tax owed). Use type="full" to refund the whole transaction, or type="partial" with line_items (each keyed by reference_product_id) for a partial refund. Numeral: POST /tax/refunds.

NameTypeReqDescription
line_itemsarrayRequired for type="partial": the line items to refund.
refund_processed_atnumberUnix timestamp (SECONDS) the refund was made. Defaults to now if omitted.
transaction_idstringyesThe transaction id (tr_...) to refund.
typestringyes"full" refunds the whole transaction; "partial" requires line_items.

No output schema declared.

No examples provided.

numeral_create_transaction ~137

RECORDS a completed sale as a transaction — this WRITES a live tax/compliance record used for filings. Supply the `calculation_id` returned by numeral_calculate_tax and your `reference_order_id`. Numeral: POST /tax/transactions.

NameTypeReqDescription
calculation_idstringyesThe calculation id returned by numeral_calculate_tax.
metadataobjectArbitrary string key/value metadata.
reference_order_idstringyesYour order id for this sale (used for record keeping / dedupe).
transaction_processed_atnumberUnix timestamp (SECONDS) the sale was processed. Defaults to now if omitted.

No output schema declared.

No examples provided.

numeral_get_customer ~124

Get a customer by id. By default `customer_id` is the Numeral id (cus_...); set id_type to "reference" to look up by your own reference_customer_id. Returns name, email, and tax-exempt status. Numeral: GET /tax/customers/{customer_id}.

NameTypeReqDescription
customer_idstringyesThe customer id — a Numeral id (cus_...) by default, or your reference id when id_type="reference".
id_typestringWhich id space `customer_id` is in (default: numeral).

No output schema declared.

No examples provided.

numeral_get_product ~69

Get a single product by its reference_product_id (your id). Returns the product's name, product_category, and timestamps. Numeral: GET /tax/products/{reference_product_id}.

NameTypeReqDescription
reference_product_idstringyesYour product id (the reference_product_id used when the product was created).

No output schema declared.

No examples provided.

numeral_get_transaction ~64

Get a recorded transaction by its Numeral id (tr_...). Returns the transaction with its line items, currencies, and metadata. Numeral: GET /tax/transactions/{transaction_id}.

NameTypeReqDescription
transaction_idstringyesThe Numeral transaction id (tr_...).

No output schema declared.

No examples provided.

numeral_list_products ~84

List your Numeral products (up to 50 per page), each with its reference id, name, and product_category. Use `cursor` (the last_product_id from a previous page) to paginate; has_more indicates more pages. Numeral: GET /tax/products.

NameTypeReqDescription
cursorstringPagination cursor — pass the last_product_id from the previous page.

No output schema declared.

No examples provided.

numeral_list_transaction_refunds ~58

List all refunds recorded against a transaction. Returns {refunds:[...]}. Numeral: GET /tax/transactions/{transaction_id}/refunds.

NameTypeReqDescription
transaction_idstringyesThe Numeral transaction id (tr_...).

No output schema declared.

No examples provided.

numeral_ping ~41

Health check — verifies the API key works and reports the environment (test/prod), api_version, and server timestamp. Numeral: GET /tax/ping.

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.