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

Read-only probes

MCP server · Payments & trading

SendCheck — EVM address verification (x402)

By api.pennyforge.org

Pre-send EVM address checks: free pre-check, $0.01 check, $0.05 deep scan. x402: payment is auth.

Source codeFinance & payments
Connect to SendCheck — EVM address verification (x402)
Checks passed
12 / 22

2 failed · 8 not measured

Median response
42 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
3

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?
312

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 42 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-06-18, serverInfo.name sendcheck.

  • Pass
    Lists tools

    tools/list returned 3 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 42 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 42 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

    6 of 6 parameters have a description (100%). The bar is 80%.

  • Fail
    Safety hints

    3 tools set neither readOnlyHint nor 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.

  • 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 2026-09-08T17:31:20.524487Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using SendCheck — EVM address verification (x402)

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 sendcheck-evm-address-verification-x402 https://api.pennyforge.org/mcp

Capabilities

Tools 3

check_address

Paid pre-send verification of one EVM address on one chain ($0.01 USDC via x402, EIP-3009 on Base): checksum, wallet-vs-contract, outgoing activity, native/USDC/USDT balances, leveled verdict with reasons and next action. TWO-PHASE: call without x_payment first to get the exact payment challenge (payTo, amount, asset), sign the USDC transfer, then call again with x_payment = the resulting X-Payment header to get the report. No account, no API key — the payment is the authentication.

Discovered
deep_scan

Paid deep scan: the full verification across ALL FIVE chains (Base, Ethereum, Arbitrum, Optimism, Polygon) incl. wrong-network detection and USDC/USDT token-mismatch flags ($0.05 USDC via x402, EIP-3009 on Base). TWO-PHASE like check_address: first call returns the payment challenge; second call with x_payment returns the report.

Discovered
validate_address

FREE pre-send check of an EVM address: EIP-55 checksum verification (catches typos, dropped characters, clipboard malware) + a note that a passing checksum is a spell-check, not payee verification. Run this before paying for check_address.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected42 ms3

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