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Evidence for your next connection.

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

Read-only probes

MCP server · Payments & trading

Arc & Ledger Tax Reference

Read-only US tax reference for notices, deadlines, filing screens, and clearly labeled estimates.

Checks passed
15 / 22

0 failed · 7 not measured

Median response
79 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
13

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
103
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 62 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name arc-ledger-mcp.

  • Pass
    Lists tools

    tools/list returned 13 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 79 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 93 ms over 2 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    2 of 2 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Pass
    Stable tool list

    No tool was removed and no required parameter was added in the last 30 days.

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

    60 of 60 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 2026-07-28T18:48:56.64232Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using Arc & Ledger Tax Reference

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 arc-ledger-tax-reference https://mcp.arcandledger.com/directory/mcp

Capabilities

Tools 13

check_5472_obligation

Use to screen common Form 5472 triggers for a foreign-owned US disregarded entity or corporation. The result is a general filing screen and does not prepare or file the form.

Discovered
check_fbar_fatca

Use to screen general FBAR and Form 8938 thresholds from aggregate balance, filing status, residence, and account-count facts. Do not request account numbers, institution names, or statements.

Discovered
check_itin_eligibility

Use to screen general ITIN reason categories, whether a return is commonly attached, and supporting-document requirements. Never request or process an actual ITIN, passport, or identity document.

Discovered
check_resolution_options

Use to screen general IRS payment and collection alternatives from a rough balance, filing-compliance status, ability-to-pay category, and coarse tax-account type when known. This is an educational fit screen, not a promise that the IRS will approve an option.

Discovered
check_treaty_withholding

Use to explain general US withholding rules, documentation, and supported US-Turkey treaty rates for a payment category. Treaty eligibility and source rules depend on the full facts.

Discovered
deadline_calendar

Use to return common federal filing and payment dates for a selected filer or entity type. The user must verify the date for weekends, holidays, extensions, fiscal years, and special facts.

Discovered
decode_irs_notice

Use when a user provides the code from an IRS notice or letter and wants a general explanation, the usual response window, or the next procedural step. Do not request the notice itself or any taxpayer identifier.

Discovered
estimate_accountable_plan

Use to estimate potentially reimbursable business expenses under an accountable-plan scenario, including the split 2026 business-mileage rates. The result does not establish a plan or determine substantiation.

Discovered
estimate_augusta_rule

Use to screen the fewer-than-15-days home-rental rule under IRC 280A(g) and calculate conditional amounts. Keep the owner-side income exclusion separate from the business-side requirements for ordinary and necessary use and reasonable rent.

Discovered
estimate_irs_penalty

Use to estimate selected federal failure-to-file, failure-to-pay, and underpayment amounts from nonidentifying figures. The result is an estimate and does not replace an IRS account transcript.

Discovered
estimate_quarterly_taxes

Use to estimate federal quarterly tax payments from nonidentifying income, entity, withholding, and prior-year tax figures. Return the assumptions, safe-harbor context, and due dates.

Discovered
estimate_rental_income

Use to estimate a basic rental-income result from nonidentifying figures and identify the modeled depreciation, passive-loss, and personal-use limitations.

Discovered
explain_tax_document

Use when a user names a US tax form or information document and wants to understand its purpose, common fields, or usual return treatment. Do not request or accept the document itself.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected62 ms13
Connected95 ms13