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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 · Communication & messaging

com.postboxservices/postbox-tools

By postboxservices.com Verified namespace

Free email checks: 24 blacklists, spoofing grade, redirects, spam test, WHOIS, BIMI, AI readiness.

WebsiteProductivity & docs
Connect to com.postboxservices/postbox-tools
Checks passed
13 / 22

1 failed · 8 not measured

Median response
767 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
10

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?
400
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 767 ms.

  • Pass
    Valid handshake

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

  • Pass
    Lists tools

    tools/list returned 10 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 767 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 767 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%.

  • 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.

  • 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 2026-11-05T19:10:06.346998Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using com.postboxservices/postbox-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 com-postboxservices-postbox-tools https://mcp.postboxservices.com/mcp

Capabilities

Tools 10

analyze_eml

Run a deliverability/content analysis on a raw RFC 822 email (.eml source: full headers + body). IMPORTANT LIMITS: with no live SMTP session, SPF, blacklist and reverse-DNS cannot be verified from a file - for the authoritative score use create_mailtest instead.

Discovered
check_ai_discoverability

Grade how discoverable a website is to AI answer engines (ChatGPT search, Perplexity, Claude, Google AI Overviews, Copilot and others) from its public files: robots.txt access for each major AI crawler (answer-engine vs training), sitemap.xml, plus llms.txt and ai.txt as informational signals. Returns an A-F grade, per-crawler access and findings.

Discovered
check_bimi

Check a domain's BIMI setup: looks up the default._bimi TXT record, fetches the logo it points to (l=) and validates the SVG against the BIMI SVG Tiny Portable/Secure profile, and reports whether a certificate (a=, VMC or CMC) is referenced. Does not verify the certificate itself or the DMARC policy (BIMI also needs DMARC at enforcement - use check_spoofability for that).

Discovered
check_blacklist

Check a domain against domain blacklists (Spamhaus DBL, SURBL, URIBL and others), or an IP address against 24 IP blacklists including Spamhaus ZEN, Barracuda and SpamCop. Checks the exact target given: domains are not resolved to IPs. Returns per-list listing status.

Discovered
check_spoofability

Grade how exposed a domain is to email spoofing and business email compromise, from its public DNS (SPF, DMARC policy strength, alignment, live lookalike domains). Returns an A-F grade with findings.

Discovered
create_mailtest

Create a disposable test address for a full email deliverability audit (score /10: SPF, DKIM, DMARC + alignment, blacklists, reverse DNS, SpamAssassin content, Gmail/Yahoo bulk-sender compliance). The USER must then send an email from the system they want to test to the returned address, after which get_mailtest_result returns the score.

Discovered
get_domain_age

Get a domain's registration date and age (young domains have weak sending reputation).

Discovered
get_mailtest_result

Fetch the score and breakdown of a mail test created with create_mailtest, once the user has sent their email to the disposable address.

Discovered
trace_redirect

Follow a URL server-side through every HTTP redirect hop to its real final destination - per-hop status, IP, TLS and timing, plus phishing/deliverability flags (cross-domain jumps, https downgrades, meta/JS redirects). Fetching is SSRF-hardened (private ranges blocked, HTTPS-only, per-hop validation); how it works: https://redirect.postboxservices.com/

Discovered
whois_lookup

WHOIS summary for a domain: registrar, created/updated/expires dates, nameservers, DNSSEC, status flags.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected767 ms10

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