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

Read-only probes

MCP server · Code & DevOps

US Sales Tax Economic Nexus Check

By Nero-Engine

Which US states must a remote seller register in for sales tax? Every state's nexus rule. Sourced.

WebsiteSource codeFinance & payments
Connect to US Sales Tax Economic Nexus Check
Checks passed
11 / 22

3 failed · 8 not measured

Median response
87 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
4

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Outdated check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?
222

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 87 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-06-18, serverInfo.name nerolabs-us-sales-tax-nexus.

  • Pass
    Lists tools

    tools/list returned 4 tools.

  • Pass
    Current protocol

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

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 87 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 87 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

    9 of 9 parameters have a description (100%). The bar is 80%.

  • Fail
    Safety hints

    4 tools set neither readOnlyHint nor destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Not measured
    Website matches publisher

    This namespace is not a reverse domain, so the website comparison does not apply.

  • Fail
    Source repo linked

    No repository URL is on file.

  • Fail
    Repo owner matches

    The GitHub repository owner does not match the namespace login.

  • Pass
    Recently updated

    Updated 2026-10-10T13:22:17.818445Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using US Sales Tax Economic Nexus Check

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 us-sales-tax-economic-nexus-check https://us-sales-tax-nexus.nerolabs.workers.dev/mcp

Capabilities

Tools 4

check_economic_nexus

Checks which US states a remote seller (no office, staff or stock in the state) must register in to collect sales tax, from its sales into each state. Give sales_by_state with the dollar sales and number of transactions (orders) per state, the period those figures cover, and whether they include sales made through marketplaces such as Amazon or Etsy. Returns states where the seller is over the economic nexus threshold (must register), states close to it (80 percent or more), states under it, and for each the threshold, the measurement period the state uses, what sales count (gross, retail or taxable only), whether marketplace sales count, when registration must happen, and the state revenue department source. Unclear cases give the SAFE answer (treated as over) with what it depends on. Free.

Discovered
list_capabilities

Lists coverage (45 sales tax states plus DC, and the 5 states with no statewide sales tax), the date the data was last checked, and related Nero Labs Rules servers. Free.

Discovered
list_nexus_thresholds

Lists the economic nexus threshold of every US sales tax state (or one state) on a date: dollar and transaction thresholds, and/or logic, measurement period, what counts, marketplace rules, when to register and the official source. Also lists the states with no statewide sales tax. Free.

Discovered
list_upcoming_nexus_changes

Lists economic nexus threshold changes in a date window (for example states dropping the 200 transaction test), soonest first, with the old and new rule and source. Use a past from_date to see recent changes. Free.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected87 ms4

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