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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

Powerline Email Tools

By powerline.ai Verified namespace

Email deliverability checks: SPF, DKIM, DMARC, BIMI, MTA-STS, blacklists, headers, spam words

WebsiteProductivity & docs
Connect to Powerline Email Tools
Checks passed
13 / 22

1 failed · 8 not measured

Median response
141 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
5

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Outdated check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?
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 141 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-06-18, serverInfo.name powerline-email-tools.

  • Pass
    Lists tools

    tools/list returned 5 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 141 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 141 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 11 parameters have a description (82%). 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 2026-10-02T05:34:20.10993Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using Powerline Email 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 powerline-email-tools https://powerline.ai/mcp

Capabilities

Tools 5

analyze_headers

Parse raw email headers: the Received delivery path with per-hop delays, the receiving server's SPF/DKIM/DMARC verdicts, DMARC alignment of the From domain, DKIM signatures, the sending IP, and bulk-sender requirements such as one-click unsubscribe.

Discovered
check_blacklists

Check an IPv4 address against about 18 IP blacklists (SpamCop, Barracuda, UCEPROTECT, PSBL, Mailspike, ...) or a domain against domain blacklists. Each list is verified with its test entries first, so lists that refuse public resolvers (such as Spamhaus) are reported as unavailable rather than clean.

Discovered
check_domain

Run every email-authentication check on a domain (SPF, DKIM, DMARC, MX, MTA-STS, TLS-RPT, BIMI, plus domain and mail-server blacklists) and return a score out of 100, per-check findings and a prioritized fix list. Use this first when asked whether a domain is set up correctly to send email.

Discovered
check_record

Look up and validate a single email DNS record for a domain, explaining each tag. record is one of spf, dmarc, dkim, bimi, mta-sts, tls-rpt, mx. SPF counts the 10-lookup limit; DMARC checks policy, reporting and external report authorization; DKIM sizes the key; MTA-STS fetches the policy file and compares it with the MX hosts; BIMI checks the logo (SVG Tiny PS) and mark certificate.

Discovered
check_spam_words

Scan an email subject and body (plain text or HTML) for spam-trigger phrases by category, ALL-CAPS, exclamation runs, emoji, URL shorteners and image-heavy HTML. Returns a low/medium/high risk reading and, optionally, a rule-based rewrite.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected141 ms5

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