Atlas / MCP servers / nspady / Google Calendar

Google CalendarBLOCK

Name: Google Calendar
Author: nspady

mcp/nspady/google-calendar-4

MCP server by nspady · Audited 2026-09-25

⚑ Report / re-scan Source ↗

MCP integration for Google Calendar to manage events.

Verdict

BLOCK

Grade

Trust score

69 /100

Exposed tools

13 9r · 3w · 1d

Transport

stdio · streamable-http

License

MIT

Stars

1,188

Overview

From the repository's own README, as read at the audited commit. Badges and raw HTML are left out.

A Model Context Protocol (MCP) server that provides Google Calendar integration for AI assistants like Claude.

I built Cocal as a separate hosted calendar assistant, taking this project further with a full visual calendar inside your chat with Claude. Connect your Google accounts without creating a Google Cloud project or running a server.

Plan across accounts. Check availability and catch conflicts across your work, personal, and shared Google Calendars in one conversation. Use it on desktop and mobile. See and manage your calendars in Claude on web, desktop, iOS, and Android. Carry your preferences into new chats. Save rules like “no meetings before 10” or which calendar to use for personal plans.

Real Cocal UI with sample calendar data. Click either screenshot to enlarge. Try Cocal →

Features

Multi-Account Support: Connect multiple Google accounts (e.g., work, personal) and query them simultaneously
*Multi-Calendar Support

Read from source at commit 2a4338dad310OBSERVED · 2026-09-25

Connect

Built from this server's own package name, version and transport as found in its source — not copied from anyone's documentation, so it cannot drift against a page we do not control. Replace the environment placeholders with a token scoped to the least it needs.

claude-code

claude mcp add google-calendar-mcp --env CLAUDE_API_KEY=${CLAUDE_API_KEY} --env GOOGLE_CALENDAR_MCP_TOKEN_PATH=${GOOGLE_CALENDAR_MCP_TOKEN_PATH} --env GOOGLE_OAUTH_CREDENTIALS=${GOOGLE_OAUTH_CREDENTIALS} --env OPENAI_API_KEY=${OPENAI_API_KEY} -- npx -y @cocal/[email protected]

claude-desktop

{
  "mcpServers": {
    "google-calendar-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@cocal/[email protected]"
      ],
      "env": {
        "CLAUDE_API_KEY": "${CLAUDE_API_KEY}",
        "GOOGLE_CALENDAR_MCP_TOKEN_PATH": "${GOOGLE_CALENDAR_MCP_TOKEN_PATH}",
        "GOOGLE_OAUTH_CREDENTIALS": "${GOOGLE_OAUTH_CREDENTIALS}",
        "OPENAI_API_KEY": "${OPENAI_API_KEY}"
      }
    }
  }
}

Exposed tools (13)

9 read · 3 write · 1 destructive. Blast radius: 1 tool can delete or overwrite — an agent that can be talked into calling a tool can be talked into calling this one.

Tool	Risk	Description
`create-event`	write	Create a new calendar event.
`create-events`	write	Create multiple calendar events in bulk. Accepts shared defaults (account, calendarId, timeZone) that apply to all events, with per-event overrides. Skips conflict and duplicate detection for speed.
`delete-event`	destructive	Delete a calendar event.
`get-current-time`	read	Get the current date and time. Call this FIRST before creating, updating, or searching for events to ensure you have accurate date context for scheduling.
`get-event`	read	Get details of a specific event by ID.
`get-freebusy`	read	Query free/busy information for calendars. Note: Time range is limited to a maximum of 3 months between timeMin and timeMax.
`list-calendars`	read	List all available calendars
`list-colors`	read	List available color IDs and their meanings for calendar events
`list-events`	read	List events from one or more calendars. Supports both calendar IDs and calendar names.
`manage-accounts`	read
`respond-to-event`	read	Respond to a calendar event invitation with Accept, Decline, Maybe (Tentative), or No Response.
`search-events`	read	Search for events in a calendar by text query.
`update-event`	write	Update an existing calendar event with recurring event modification scope support.

Trust audit

BLOCKgrade D · trust 69/100 Do not install this without reading the findings. The audit found something that could harm you or your machine.

Layer	What it checks	Result
L0	Provenance & inventory	PASS
L1	Static analysis of the code	FAIL
L2	Instruction surface (what it tells the agent)	PASS
L3	Class-specific surface	WARN
L4	Behavioural (sandbox)	SKIPPED

What the source does

Filesystem: declared (6 observation(s))
Network: declared (3 observation(s))
Shell: none-observed
Dependencies: not all pinned
Secrets in source: none-found

Findings (21)

HIGHSupply chain · supply.typosquat · CWE-829, CWE-1357

package.json

gaxios ~ axios

Why it matters. dependency name one edit from a popular package

Fix. verify the package; likely typosquat

MEDIUMNetwork egress · net.beacon_words · CWE-200, CWE-319

src/handlers/core/ManageAccountsHandler.ts:236

callback_url: started.callbackUrl!,

MEDIUMNetwork egress · net.beacon_words · CWE-200, CWE-319

src/types/structured-responses.ts:420

callback_url?: string;

MEDIUMFilesystem / path · mcp.destructive_tools · CWE-22, CWE-59

delete-event

Why it matters. 1 tool(s) can delete or overwrite

Fix. prefer a read-only mode or scoped tokens; the page states the blast radius

LOWInventory / provenance · inv.hidden_file · CWE-1104

.cursorignore

.cursorignore

Why it matters. hidden member outside the usual dotfiles

Fix. review its purpose

LOWInventory / provenance · inv.hidden_file · CWE-1104

.release-please-manifest.json

.release-please-manifest.json

Why it matters. hidden member outside the usual dotfiles

Fix. review its purpose

LOWInformation disclosure · disclose.log_secret · CWE-209, CWE-532

src/tests/unit/schemas/tool-description-analysis.test.ts:243

console.log(`\nTotal token count: ${analysisReport.totalTokens.toLocaleString()}`);

LOWFilesystem / path · fs.traversal · CWE-22, CWE-59

src/handlers/core/BaseToolHandler.ts:5

import { getCredentialsProjectId } from "../../auth/utils.js";

LOWFilesystem / path · fs.traversal · CWE-22, CWE-59

src/handlers/core/BaseToolHandler.ts:6

import { CalendarRegistry } from "../../services/CalendarRegistry.js";

LOWFilesystem / path · fs.traversal · CWE-22, CWE-59

src/handlers/core/BaseToolHandler.ts:7

import { validateAccountId } from "../../auth/paths.js";

LOWFilesystem / path · fs.traversal · CWE-22, CWE-59

src/handlers/core/BaseToolHandler.ts:8

import { convertToRFC3339 } from "../../utils/datetime.js";

LOWFilesystem / path · fs.traversal · CWE-22, CWE-59

src/handlers/core/BaseToolHandler.ts:9

import { isCalendarNotAccessibleError } from "../../utils/google-api-errors.js";

LOWNetwork egress · net.beacon_words · CWE-200, CWE-319

src/tests/unit/handlers/ManageAccountsHandler.test.ts:204

expect(response.callback_url).toContain('oauth2callback');