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

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MCP server · Code & DevOps

Retainful MCP by usefulapi

By usefulapi.io Verified namespace

List contacts and lists; create contacts, add them to lists and record events in Retainful.

WebsiteSource code
Connect to Retainful MCP by usefulapi
Checks passed
14 / 22

0 failed · 8 not measured

Median response
64 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
7

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Outdated check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 64 ms.

  • Pass
    Valid handshake

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

  • Pass
    Lists tools

    tools/list returned 7 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 64 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 64 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

    25 of 29 parameters have a description (86%). 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 2026-11-10T23:35:03.831389Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using Retainful 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 retainful-mcp-by-usefulapi https://retainful.usefulapi.io/mcp

Capabilities

Tools 7

retainful_add_contact_to_list

WRITE: create or update a contact by email and add them to a list in one call. A list can start an automation. email_opt_in is required: an existing contact is set to SUBSCRIBED when it is omitted here. Retainful API: POST /contact-groups/{listId}/contacts.

Discovered
retainful_get_contact

Get one contact (profile) by its Retainful id (contactUUID), with its attributes. Retainful API: GET /customer/{id}.

Discovered
retainful_get_list

Get one list or segment by its id. Retainful API: GET /contact-groups/{id}.

Discovered
retainful_list_contacts

List contacts (profiles) in the Retainful organization, one page at a time, with consent status and source. Retainful API: GET /customer.

Discovered
retainful_list_lists

List the lists and segments in the organization with their ids. Use the id as list_id in retainful_add_contact_to_list. Retainful API: GET /contact-groups.

Discovered
retainful_track_event

WRITE: record one event on a contact's timeline. Automations triggered by the event can email the contact. Reuse the same unique_identifier only for a retry of the same real occurrence (a repeat does not trigger automations again); use a new one for each new occurrence. Event data must be flat: strings, numbers, or booleans. Retainful API: POST /events.

Discovered
retainful_upsert_contact

WRITE: create a contact, or update it when the email or phone already exists. Does not add anyone to a list. email_opt_in is required: it sets marketing consent, so send SUBSCRIBED only with real consent. Needs email or phone. Retainful API: POST /customer/create.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected64 ms7

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