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io.usefulapi/cronofy

REMOTE · CRONOFY.USEFULAPI.IO · SCANNED SEP 21

MCP server for Cronofy — read calendars, events and free/busy, and create, update or delete events.

Available components

remote · cronofy.usefulapi.io 18
0 this week 18 Trust /100
Trust breakdown (7 categories)

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →

Endpoint Security46
Transport & Reachability0
Schema Quality & AI Usability0
  • Schema not yet verified: we couldn't read the endpoint's schema.Unverified
Stability & Change Management0
  • Stability not yet verified: not enough scan history yet (needs a 30-day window).Unverified
Tool Coverage0
  • Tool coverage not yet verified: we couldn't read the endpoint's tools.Unverified
Tool Safety0
  • Tool safety not yet verified: we couldn't read the endpoint's tools.Unverified
Capabilities0
  • Capabilities not yet verified: we couldn't read the endpoint's capabilities.Unverified

Unverified: 5 categories

Categories scored 0 because we could not verify them: authentication we do not have, an unreachable endpoint, or not enough scan history. We only credit what we can confirm.

Install

How do I install the io.usefulapi/cronofy MCP server?

io.usefulapi/cronofy is a hosted endpoint at https://cronofy.usefulapi.io/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

remote · cronofy.usefulapi.io

# add to Claude Code
claude mcp add --transport http io-usefulapi-cronofy 'https://cronofy.usefulapi.io/mcp'
// .cursor/mcp.json
{
  "mcpServers": {
    "io-usefulapi-cronofy": {
      "url": "https://cronofy.usefulapi.io/mcp"
    }
  }
}
// .vscode/mcp.json
{
  "servers": {
    "io-usefulapi-cronofy": {
      "type": "http",
      "url": "https://cronofy.usefulapi.io/mcp"
    }
  }
}
# ~/.codex/config.toml
[mcp_servers.io-usefulapi-cronofy]
url = "https://cronofy.usefulapi.io/mcp"
// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "io-usefulapi-cronofy": {
      "type": "remote",
      "url": "https://cronofy.usefulapi.io/mcp",
      "enabled": true
    }
  }
}
# add to OpenClaw
openclaw mcp add io-usefulapi-cronofy --url 'https://cronofy.usefulapi.io/mcp' --transport streamable-http
# ~/.hermes/config.yaml
mcp_servers:
  io-usefulapi-cronofy:
    url: "https://cronofy.usefulapi.io/mcp"
// ~/.netclaw/config/netclaw.json
{
  "McpServers": {
    "io-usefulapi-cronofy": {
      "Transport": "http",
      "Url": "https://cronofy.usefulapi.io/mcp"
    }
  }
}
# add to Vellum
assistant mcp add io-usefulapi-cronofy -t streamable-http -u 'https://cronofy.usefulapi.io/mcp'
// mcp.json
{
  "mcpServers": {
    "io-usefulapi-cronofy": {
      "type": "http",
      "url": "https://cronofy.usefulapi.io/mcp"
    }
  }
}

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

Changelog

Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.

  • 26 Aug 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 14 Aug 26 0
    • Endpoint reachability: reachable → not serving MCP ▼ security
    • Stability: 0.57 → unverified ▼ security
    • Authorization: pass → unverified ▼ security
    • Transport: pass → fail ▼ security
    • Capabilities: fail → unverified ▼ functional
    • Tool coverage: 100 → unverified ▼ functional
  • 13 Aug 26 0
    • Transport: unverified → pass ▲ security
    • Authorization: unverified → pass ▲ security
    • MCP protocol: unverified → fail ▼ functional
    • Endpoint reachability: not serving MCP → reachable ▲ functional
    • Tool coverage: unverified → 100 ▲ functional
    • Stability: unverified → 0.57 ▲ functional
  • 12 Aug 26 0
    • Transport: fail → unverified ▼ security
  • 11 Aug 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 3 Aug 26 0
    • Endpoint reachability: reachable → not serving MCP ▼ security
    • Authorization: pass → unverified ▼ security
    • Stability: 0.20 → unverified ▼ security
    • Transport: pass → fail ▼ security
    • Capabilities: fail → unverified ▼ functional
    • Tool coverage: 100 → unverified ▼ functional
  • 2 Aug 26 0
    • Authorization: unverified → pass ▲ security
    • Transport: fail → pass ▲ security
    • MCP protocol: unverified → fail ▼ functional
    • Endpoint reachability: not serving MCP → reachable ▲ functional
    • Tool coverage: unverified → 100 ▲ functional
    • Stability: unverified → 0.20 ▲ functional
  • 1 Aug 26 0
    • Endpoint reachability: reachable → not serving MCP ▼ security
    • Stability: 0.13 → unverified ▼ security
    • Authorization: pass → unverified ▼ security
    • Transport: pass → fail ▼ security
    • Capabilities: fail → unverified ▼ functional
    • Tool coverage: 100 → unverified ▼ functional
Diagnostics

Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.

Captured 21 Sept 2026 · Probed https://cronofy.usefulapi.io/mcp

TLS valid

Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .

Subject Issuer Valid from Valid until Key Signature Serial
CN=usefulapi.io CN=WE1,O=Google Trust Services,C=US 14 Sept 2026 13 Dec 2026 ECDSA 256 ECDSA-SHA256 c7c72db6aad2f08c0e998b93b1857e20
SANs: usefulapi.io, cronofy.usefulapi.io, *.cronofy.usefulapi.io
CN=WE1,O=Google Trust Services,C=US (CA) CN=GTS Root R4,O=Google Trust Services LLC,C=US 13 Dec 2023 20 Feb 2029 ECDSA 256 ECDSA-SHA384 7ff31977972c224a76155d13b6d685e3
CN=GTS Root R4,O=Google Trust Services LLC,C=US (CA) CN=GlobalSign Root CA,OU=Root CA,O=GlobalSign nv-sa,C=BE 15 Nov 2023 28 Jan 2028 ECDSA 384 SHA256-RSA 7fe530bf331343bedd821610493d8a1b

Background: What to check on a remote MCP endpoint →

DNSSEC insecure

Validation of cronofy.usefulapi.io. — Not signed

Zone DS Keys Algorithms Outcome
. trust_anchor 20326, 38696 8, 8 Verified
io. present 57355 8 Verified
usefulapi.io. absent Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation
Authentication No authorisation required

The endpoint answered without asking for a token. Anyone who knows the URL can reach it.

Result No authorisation required
HTTP status 429
Header Value
x-frame-options SAMEORIGIN
referrer-policy same-origin

Background: How OAuth 2.1 works in the 2026 MCP spec →

Transports 2 probes
Transport URL Outcome Status Location
streamable-http https://cronofy.usefulapi.io/mcp HTTP error 429
http (plaintext) http://cronofy.usefulapi.io/mcp Inconclusive 429
MCP tools · 8 exposed · ~810 tokens

The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →

Tool Tokens
cronofy_delete_event ~79

Deletes an event (by your event_id) from a real connected calendar. Destructive. API: DELETE /v1/calendars/{calendar_id}/events.

NameTypeReqDescription
calendar_idstringyesCalendar id the event lives on.
event_idstringyesYOUR event_id for the event to delete (sent in the JSON body).

No output schema declared.

No examples provided.

cronofy_get_account ~39

Get the authenticated Cronofy account's details (id, email, name, default tzid, locale). API: GET /v1/account.

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

cronofy_get_free_busy ~156

Read free/busy information across the account's calendars over a time window. Returns { pages, free_busy }. API: GET /v1/free_busy.

NameTypeReqDescription
calendar_idsarray–Restrict to these calendar ids (sent as repeated calendar_ids[] params).
fromstring–Start of the window — date (yyyy-mm-dd) or ISO 8601 datetime.
include_managedboolean–Include events created via the Cronofy API. Default false.
tostring–End of the window — date (yyyy-mm-dd) or ISO 8601 datetime.
tzidstringyesREQUIRED time zone id for the response, e.g. "Etc/UTC".

No output schema declared.

No examples provided.

cronofy_get_userinfo ~40

Get the OpenID-style profile of the authenticated user (sub, email, Cronofy profile info). API: GET /v1/userinfo.

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

cronofy_list_calendars ~41

List all calendars the authenticated account can see (id, name, profile, readonly, primary). API: GET /v1/calendars.

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

cronofy_list_profiles ~43

List the connected calendar accounts/profiles (e.g. Google, Office 365) linked to this Cronofy account. API: GET /v1/profiles.

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

cronofy_read_events ~210

Read events across the account's calendars over a time window. Returns { pages, events }. API: GET /v1/events.

NameTypeReqDescription
calendar_idsarray–Restrict to these calendar ids (sent as repeated calendar_ids[] params).
fromstring–Start of the window — date (yyyy-mm-dd) or ISO 8601 datetime.
include_deletedboolean–Include deleted events. Default false.
include_managedboolean–Include events created via the Cronofy API. Default false.
last_modifiedstring–Only events modified since this ISO 8601 datetime.
only_managedboolean–Return only events created via the Cronofy API. Default false.
tostring–End of the window — date (yyyy-mm-dd) or ISO 8601 datetime.
tzidstringyesREQUIRED time zone id for the response, e.g. "Etc/UTC" or "America/New_York".

No output schema declared.

No examples provided.

cronofy_upsert_event ~202

Creates or updates an event on a REAL connected calendar (upsert by event_id). This writes to the user's actual calendar. API: POST /v1/calendars/{calendar_id}/events.

NameTypeReqDescription
calendar_idstringyesTarget calendar id (from cronofy_list_calendars).
descriptionstring–Event description/body.
endstringyesEvent end — ISO 8601 datetime or a date (yyyy-mm-dd) string.
event_idstringyesYOUR unique id for the event. Re-using it updates the same event.
location_descriptionstring–Free-text location (sent as location.description).
startstringyesEvent start — ISO 8601 datetime or a date (yyyy-mm-dd) string.
summarystringyesEvent title/summary.
tzidstring–Time zone id for the start/end, e.g. "America/New_York".

No output schema declared.

No examples provided.

Common questions

What is the io.usefulapi/cronofy MCP server?

io.usefulapi/cronofy is an MCP server listed in the public MCP registry as io.usefulapi/cronofy. MCP server for Cronofy, read calendars, events and free/busy, and create, update or delete events. This page covers its hosted endpoint (https://cronofy.usefulapi.io/mcp).

Is the io.usefulapi/cronofy MCP server safe to use?

io.usefulapi/cronofy scores 18 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

What tools does the io.usefulapi/cronofy MCP server expose?

io.usefulapi/cronofy exposes 8 tools: cronofy_get_account, cronofy_get_userinfo, cronofy_list_calendars, cronofy_list_profiles, cronofy_read_events, and 3 more. Their descriptions and schemas cost roughly 810 tokens of context every time the server is loaded.

Does the io.usefulapi/cronofy MCP server require authentication?

No. We connected to io.usefulapi/cronofy without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

Is the io.usefulapi/cronofy MCP server still maintained?

io.usefulapi/cronofy is still listed as active in the MCP registry. We last reached this channel on 21 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.