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

Read-only probes

MCP server · Code & DevOps

SIGNL4 MCP by usefulapi

Read SIGNL4 alerts, teams, users and duty schedules; raise, acknowledge, close and annotate alerts.

Checks passed
14 / 22

0 failed · 8 not measured

Median response
52 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
18

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Outdated check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 52 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name signl4-mcp.

  • Pass
    Lists tools

    tools/list returned 18 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 52 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 52 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

    48 of 48 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 2026-11-10T23:33:56.575481Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using SIGNL4 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 signl4-mcp-by-usefulapi https://signl4.usefulapi.io/mcp

Capabilities

Tools 18

signl4_acknowledge_alert

WRITE: acknowledge an alert on behalf of a SIGNL4 user (recorded in its history under that user). Stops escalation to further tiers for that alert. POST /v3/signls/{signlId}/acknowledge.

Discovered
signl4_annotate_alert

WRITE: add a text note to an alert's timeline on behalf of a SIGNL4 user. The note is visible to the team in the app. It does not page anyone by itself. POST /v3/signls/{signlId}/annotate.

Discovered
signl4_close_alert

WRITE: close (resolve) an alert on behalf of a SIGNL4 user; it leaves the open list and stops all further notifications. POST /v3/signls/{signlId}/close.

Discovered
signl4_get_alert

Full detail of one alert: title, text, severity, category, status and delivery status, history (who acknowledged/closed it and when), parameters, attachments and escalations with per-user delivery. GET /v3/signls/{signlId}/details.

Discovered
signl4_get_alert_report

Alert volume and response statistics per team over several time periods: acknowledged, closed and unhandled counts, overall and per category (optionally for one user). Teams that cannot be read are reported under `errors`. GET /v3/signls/report.

Discovered
signl4_get_alert_timeline

The ordered timeline of an alert: creation, notifications, acknowledgements, annotations, escalations and remote actions. GET /v3/signls/{signlId}/timeline.

Discovered
signl4_get_duty_status

Whether a user is currently on or off duty in each of their teams (dutyMode, onDutyTime, tier). GET /v3/users/{userId}/dutyStatus.

Discovered
signl4_get_duty_summary

Duty assistant info per team: whether it is enabled and the last two (or all) duty periods. GET /v3/duties/summary.

Discovered
signl4_get_team

One SIGNL4 team: name, description, time zone, member ids. GET /v3/teams/{teamId}.

Discovered
signl4_get_user

One SIGNL4 user: name, e-mail, contact addresses, time zone and duty status per team. GET /v3/users/{userId}.

Discovered
signl4_list_alerts

Search SIGNL4 alerts (signls), newest first, with status, severity, category and history (created, acknowledged, closed). Filter by team, status, creation time, text or external id. Up to 100 per page; pass the returned continuation_token to get the next page. POST /v3/signls/paged (a read).

Discovered
signl4_list_audit_logs

Audit log of changes and events in the SIGNL4 subscription (who changed what, when). Filter by team, time window and message text; pass the returned continuation_token for the next page. GET /v3/audits.

Discovered
signl4_list_categories

List the alert categories of a team (name, color, keywords used to auto-classify alerts). The category name can be passed to signl4_raise_alert. GET /v3/categories/{teamId}.

Discovered
signl4_list_duty_schedules

Planned on-call duty schedules (who is on duty when): start/end, team, user, tier, stand-in and shift info. Filter by team, user and time window. POST /v3/schedules (a read).

Discovered
signl4_list_team_users

List the users of the given teams (all accessible teams by default) with duty status. Teams that cannot be read are reported under `errors`. GET /v3/teams/users.

Discovered
signl4_list_teams

List the SIGNL4 teams the API key can access: id, name, description, time zone and member ids. Team ids are needed to raise alerts and to look up categories and duties. GET /v3/teams.

Discovered
signl4_list_users

List the SIGNL4 users the key can access with name, e-mail, contact addresses, activation state and duty status per team (dutyMode, onDutyTime). User ids are needed to acknowledge/close/annotate alerts. GET /v3/users.

Discovered
signl4_raise_alert

WRITE: raise a new alert in a SIGNL4 team. THIS NOTIFIES REAL PEOPLE: every team member currently on duty is paged (push, SMS and/or voice call according to their settings) and the alert escalates if nobody acknowledges it. Only use it when the user clearly asked to alert the team; never for tests unless they said so. Not idempotent: a second call pages the team again. Returns the new alert incl. its id. POST /v3/signls.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected52 ms18