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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

Qualisend Email Verification

Verify email addresses and clean lists to improve deliverability and sender reputation.

Checks passed
12 / 22

2 failed · 8 not measured

Median response
281 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
12

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?
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 281 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name Qualisend.

  • Pass
    Lists tools

    tools/list returned 12 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 281 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 281 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

    24 of 24 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.

  • 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 2026-08-14T10:42:06.342413Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using Qualisend Email Verification

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 qualisend-email-verification https://app.qualisend.com/api/mcp

Capabilities

Tools 12

analyze_email_header

Read the hidden technical details of an email (its 'headers') to show the route it took, how long each step took, and whether it passed spam/authentication checks - handy for figuring out why a message was slow or went to spam. Paste the message source / 'Show original'. No credit used. Available on the Qualisend Pro plan.

Discovered
check_blacklist

Check whether a sending domain or IP is currently on any of the major email blacklists that can push your mail to spam - a point-in-time reputation check across lists like Spamhaus, SpamCop, and Barracuda. No credit used. Requires the Qualisend Blacklist Monitoring add-on. Read the result carefully: `listed_on` are confirmed listings, while `undetermined_on` are lists that did not answer (commonly Spamhaus refusing a shared resolver). `clean` is true only when every list answered and none matched, so a non-empty `undetermined_on` means those lists are UNKNOWN - do not report them as clear or as listings.

Discovered
check_disposable

Tell whether an email address is a throwaway/temporary one, a generic team inbox (like info@ or support@), or a free consumer address (like gmail) - useful for spotting low-quality sign-ups. No credit used. Available on the Qualisend Pro plan.

Discovered
check_domain

Check whether a domain is set up to send email that reaches the inbox - its mail servers plus its SPF and DMARC sender-authentication, and what's missing. A plain deliverability health check for a sending domain. No credit used. Available on the Qualisend Pro plan.

Discovered
check_typo

Spot a likely typo in an email's domain (like gmial.com) and suggest the correct one, so you don't lose contacts to misspelled addresses. No credit used. Available on the Qualisend Pro plan.

Discovered
generate_dns_record

Create the exact DNS setting a domain needs so its email is trusted and harder to spoof - SPF, DMARC, BIMI, or MTA-STS. Returns the record to copy into DNS, with where to put it. No credit used. Available on the Qualisend Pro plan.

Discovered
get_credit_balance

Return the number of verification credits available in your Qualisend workspace.

Discovered
get_verification

Look up the status and result of a verification you started, by job_id (returned from verify_email/verify_emails). For a single check it returns the final verdict once the mailbox probe completes; for a batch it returns progress + a result-mix summary.

Discovered
lookup_smtp_code

Explain a mail-server reply/error code (like 550 or 5.1.1) in plain English, and say whether it's a temporary hiccup or a permanent failure. No credit used. Available on the Qualisend Pro plan.

Discovered
verify_email

Verify a single email address - syntax, domain/MX, disposable + role detection, typo suggestion, and mailbox reachability. Returns a deliverability verdict (deliverable / risky / undeliverable / unknown). Consumes 1 credit.

Discovered
verify_emails

Verify up to 50 email addresses at once and get a deliverability verdict for each, synchronously. Consumes 1 credit per address. For larger lists (up to 1000), use verify_list.

Discovered
verify_list

Verify a large list of up to 1000 email addresses. This runs ASYNCHRONOUSLY: it creates ONE bulk job, returns a job_id immediately, and the mailbox probes run in the background. Poll get_verification with the job_id for progress and a result summary (counts by verdict). Consumes 1 credit per address. For lists larger than 1000, use the Qualisend dashboard or bulk API.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected281 ms12