MCP Chrono MCP Server

Time, calendar, timezone, and date utilities for AI agents.

README.md

mcp-chrono

MCP server providing time, calendar, timezone, Chinese lunar calendar, almanac, and date utilities for AI agents.

Quick Start

Using npx (no installation needed)

npx mcp-chrono

Global install

npm install -g mcp-chrono
mcp-chrono

Usage with MCP Clients

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "chrono": {
      "command": "npx",
      "args": ["-y", "mcp-chrono"]
    }
  }
}

Claude Code

claude mcp add chrono -- npx -y mcp-chrono

Or with a custom data directory:

claude mcp add chrono -- npx -y mcp-chrono --data-dir /path/to/data

Cursor

Add to .cursor/mcp.json in your project root:

{
  "mcpServers": {
    "chrono": {
      "command": "npx",
      "args": ["-y", "mcp-chrono"]
    }
  }
}

Windsurf

Add to ~/.codeium/windsurf/mcp_config.json:

{
  "mcpServers": {
    "chrono": {
      "command": "npx",
      "args": ["-y", "mcp-chrono"]
    }
  }
}

Generic MCP client (mcp.json)

Any MCP-compatible client can use the standard mcp.json format:

{
  "mcpServers": {
    "chrono": {
      "command": "npx",
      "args": ["-y", "mcp-chrono"],
      "transportType": "stdio"
    }
  }
}

With custom data directory:

{
  "mcpServers": {
    "chrono": {
      "command": "npx",
      "args": ["-y", "mcp-chrono", "--data-dir", "/path/to/data"],
      "transportType": "stdio"
    }
  }
}

Data Directory

Holiday API responses are cached locally to avoid repeated network requests. Default location: ~/.mcp-chrono/

Override with --data-dir:

npx mcp-chrono --data-dir /tmp/mcp-chrono-data

Tools

Time & Timezone

`get_current_time`

Get current time in any IANA timezone with detailed components (timestamp, weekday, week of year, day of year, UTC offset, etc.)

Parameter Type Required Default Description
timezone string No UTC IANA timezone (e.g. Asia/Shanghai, America/New_York)
format string No iso Output format: iso, human, or relative
`convert_timezone`

Convert a datetime between two IANA timezones.

Parameter Type Required Description
datetime string Yes ISO 8601 datetime (e.g. 2024-01-15T10:30:00)
from_timezone string Yes Source IANA timezone
to_timezone string Yes Target IANA timezone
`list_timezones`

Search IANA timezones with current offsets and Chinese city names.

Parameter Type Required Description
query string No Search by timezone name, city, or Chinese name
continent string No Filter by continent (e.g. Asia, Europe, America)
`parse_timestamp`

Parse Unix timestamps (seconds/milliseconds) or ISO 8601 strings into date components.

Parameter Type Required Default Description
input string | number Yes - Unix timestamp (seconds or milliseconds) or ISO 8601 string
timezone string No UTC IANA timezone for output

Date Calculation

`calculate_time`

Add/subtract time from a date. Returns a new date after applying the offset.

Three modes: gregorian (standard date arithmetic), lunar (Chinese calendar arithmetic), anchor (offset from a named festival like 春节 or Thanksgiving).

Parameter Type Required Default Description
mode string No gregorian Calculation mode: gregorian, lunar, or anchor
base_date string No now Base date in ISO format. Defaults to current time if omitted
timezone string No UTC IANA timezone for the base date
years integer No - Years to add (negative to subtract)
months integer No - Months to add (negative to subtract)
days integer No - Days to add (negative to subtract)
hours integer No - Hours to add (negative to subtract)
minutes integer No - Minutes to add (negative to subtract)
festival string No - Festival name for anchor mode (e.g. 春节, Christmas, Thanksgiving)
festival_year integer No - Year to resolve festival date for anchor mode
`date_diff`

Calculate the difference between two dates in years, months, days, hours, minutes, and total counts.

Parameter Type Required Default Description
start string Yes - Start date in ISO 8601 format
end string Yes - End date in ISO 8601 format
timezone string No

Tools 6

get_current_timeGet current time in any IANA timezone with detailed components.
convert_timezoneConvert a datetime between two IANA timezones.
list_timezonesSearch IANA timezones with current offsets and Chinese city names.
parse_timestampParse Unix timestamps or ISO 8601 strings into date components.
calculate_timeAdd or subtract time from a date using gregorian, lunar, or anchor modes.
date_diffCalculate the difference between two dates in various units.

Try it

What is the current time in Tokyo and how many hours ahead is it from UTC?
Convert 2024-05-20T10:00:00 from New York time to Shanghai time.
Calculate the date 3 months and 5 days after today using the Gregorian calendar.
When is the next Spring Festival (春节) and what date does it fall on in 2025?
How many days are there between January 1st, 2024 and today?

Frequently Asked Questions

What are the key features of MCP Chrono?

IANA timezone conversion and lookup. Gregorian and Chinese lunar calendar arithmetic. Festival and public holiday tracking. Unix timestamp and ISO 8601 parsing. Local caching of holiday API responses.

What can I use MCP Chrono for?

Coordinating meeting times across global teams in different timezones. Calculating project deadlines based on business days and holidays. Converting legacy Unix timestamps into human-readable formats for logs. Planning events around specific cultural festivals or lunar dates.

How do I install MCP Chrono?

Install MCP Chrono by running: npx mcp-chrono

What MCP clients work with MCP Chrono?

MCP Chrono works with any MCP-compatible client including Claude Desktop, Claude Code, Cursor, and other editors with MCP support.

Turn this server into reusable context

Keep MCP Chrono docs, env vars, and workflow notes in Conare so your agent carries them across sessions.

Open Conare