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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

Emailable MCP by usefulapi

Verify email addresses with Emailable one by one or in batches, and read credits and batch results.

Checks passed
14 / 22

0 failed · 8 not measured

Median response
62 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
4

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Outdated check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?
402

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 62 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name emailable-mcp.

  • Pass
    Lists tools

    tools/list returned 4 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 62 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 62 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

    13 of 13 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.

  • 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 2026-11-10T23:34:02.946381Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using Emailable MCP by usefulapi

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 emailable-mcp-by-usefulapi https://emailable.usefulapi.io/mcp

Capabilities

Tools 4

emailable_create_batch

SPENDS CREDITS: starts a bulk verification of up to 5000 email addresses. Emailable takes 1 credit per email when the batch is created, and if the account has too few credits it may charge the account's saved card to buy more. A test_ API key spends nothing. The batch cannot be cancelled here, and the call is never retried: if it fails or times out, check emailable_get_account before trying again, because a retry can charge twice. Returns the batch id; poll it with emailable_get_batch. Emailable's terms allow verification of opt-in subscribers' addresses. POST /v1/batch.

Discovered
emailable_get_account

The Emailable account behind this API key: the owner's email and available_credits. Check it before a large batch. GET /v1/account.

Discovered
emailable_get_batch

Status and results of a batch made with emailable_create_batch: message, progress (processed/total), reason_counts and total_counts (deliverable, undeliverable, risky, unknown). Batches of up to 1,000 emails also return the results inline in `emails` (30 days). They come in pages: up to `limit` results, fewer if the reply would get too long; ask for the next page with emails_page.next_offset. A bigger batch returns download_file, a temporary link (5 days) to a ZIP of a CSV: share it only with the account owner. Free to call. GET /v1/batch.

Discovered
emailable_verify_email

SPENDS CREDITS: verifies one email address and uses 1 Emailable credit (a test_ API key spends none). Returns state (deliverable, undeliverable, risky, unknown), reason, score (0-100), and flags: disposable, free, role, accept_all, no_reply, mailbox_full, plus did_you_mean (a typo fix), the detected user/domain/tag, mx_record and smtp_provider. A credit is returned for an unknown result. The call is never retried automatically. If the reply is {status: "try_again"}, the check took longer than the timeout: call again with the same email; repeats within 5 minutes are not charged. Emailable's terms allow verification of opt-in subscribers' addresses. GET /v1/verify.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected62 ms4