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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 · Knowledge & memory

Cuelark Tools

Exact tools for agents: US tax, routing/EIN checks, business days, JSON, links, packages, citations.

Checks passed
11 / 22

3 failed · 8 not measured

Median response
445 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
15

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?
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 445 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name cuelark-tools.

  • Pass
    Lists tools

    tools/list returned 15 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 445 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 445 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.

  • Fail
    Parameters documented

    33 of 103 parameters have a description (32%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Fail
    Website matches publisher

    The website host does not match the reverse-domain namespace.

  • Fail
    Source repo linked

    No 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 2026-11-10T13:29:34.229931Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using Cuelark Tools

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 cuelark-tools https://tools.cuelark.com/mcp

Capabilities

Tools 15

calculate

Exact decimal arithmetic for an expression (no floating-point drift: 0.1+0.2 = 0.3; + − × ÷ ^ %, sqrt, ln, log, round, min, max, pi), summary statistics for a list of numbers, rounding with a chosen mode, and adult BMI from lb/in or kg/cm.

Discovered
convert

Unit conversion (imperial and metric: length, weight, volume, area, speed, temperature, data, pressure, energy), color hex/rgb/hsl, WCAG contrast ratio, numbers in words and $ or lakh/crore formats, Markdown to HTML, pixels vs print size at a DPI, and CGPA to percentage (official formulas).

Discovered
dates

Calendar math: days between dates, add days/weeks/months/years, exact age (with exam cut-offs), business days skipping public holidays (US federal by default; UK, EU, CA, AU, IN, SG, AE), a country's holiday list, and cron schedules in plain English.

Discovered
encode

Base64 and URL encode/decode (UTF-8 safe), MD5/SHA-1/SHA-256/384/512 hashes, new UUID v4/v7 or ULID (or read a ULID's time), and decode a JWT's header and payload without verifying it.

Discovered
finance

Monthly loan payment (EMI) with a yearly amortization summary, simple and compound interest (with monthly contributions), percentage math (of, what percent, change, add, subtract), and tax added to or removed from a price at a given rate (VAT, sales tax, or India GST with CGST/SGST/IGST split).

Discovered
ifsc_lookup

Bank, branch, address, MICR and NEFT/RTGS/IMPS/UPI support for an Indian IFSC code, from RBI's published lists via Razorpay's IFSC dataset.

Discovered
income_tax

Estimate income tax from official tables. us_federal: 2025 or 2026 IRS brackets, standard deduction (with 65+/blind extras) or itemized, by filing status. india: FY 2025-26 or 2026-27, new vs old regime with 87A rebate, surcharge and cess. Each answer cites its source.

Discovered
json

Validate and pretty-print or minify JSON (errors give line and column), or convert JSON to YAML or CSV, or CSV to JSON.

Discovered
package_check

Does this package exist (catches invented names)? Latest version, deprecation, license, repository, last publish, downloads, and the newest version matching a range. Ecosystems: npm, pypi, crates.

Discovered
text

Exact text facts models get wrong: word/character/grapheme counts, whether text fits X, SMS, meta title/description or custom:N limits (with a truncated version), letter frequency, case conversion, slugs, JavaScript regex matches and replacements, lorem ipsum, and OpenAI token counts.

Discovered
time

Current time anywhere (with DST state and next clock change), convert a wall-clock time between zones, or convert Unix timestamps to and from dates. Accepts IANA zones or common names (ET, PT, UTC, London, IST).

Discovered
ui_component_lookup

Search the ui.cuelark.com shadcn/ui registry (React components, blocks, themes) and get the shadcn CLI install command for each match.

Discovered
validate

Check an identifier's format and check digit: US ABA routing number, EIN, SSN (format rules only), ZIP; card numbers (Luhn) and IBAN; India GSTIN, PAN, IFSC, UPI ID, Aadhaar (Verhoeff) and PIN code. Proves a value is well formed, not that it's registered. Nothing is stored.

Discovered
verify_citation

Check that a paper exists and get its canonical metadata (title, authors, year, venue, DOI link, retraction flag) by DOI, arXiv id, or title plus author. Uses Crossref, OpenAlex and arXiv. No abstracts.

Discovered
verify_links

Check up to 20 URLs live: HTTP status, redirects, final URL, page title and canonical, and optionally whether each page contains a quote. Respects robots.txt and refuses private addresses.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected445 ms15