Mycal

Malaysia's most complete calendar API — public holidays, school calendar, exam schedules, and MCP server for AI tools.

npm: mycal-core npm: mycal-sdk npm: mycal-mcp-server License: MIT Deploys on Cloudflare

Data source: Official government gazette (JPM BKPP), JAKIM, KPM, MPM. Not scraped from third-party websites.

Links

• Website + demo: https://mycal-web.pages.dev
• Developer docs: https://mycal-web.pages.dev/docs
• API base URL: https://mycal-api.huijun00100101.workers.dev/v1
• GitHub: https://github.com/Junhui20/malaysia-calendar-api

Packages

Published to npm under the @catlabtech scope:

Package	Purpose	Install
@catlabtech/mycal-core	Shared types, Zod schemas, and calendar/business-day logic	npm install @catlabtech/mycal-core
@catlabtech/mycal-sdk	TypeScript client SDK for the REST API	npm install @catlabtech/mycal-sdk
@catlabtech/mycal-mcp-server	MCP server exposing 13 calendar tools for AI agents	npm install @catlabtech/mycal-mcp-server

Features

• 49 public holidays for 2026 from official gazette (Warta Kerajaan) — federal + state-specific
• 16 states + 3 Federal Territories with aliases (KL, JB, Penang, etc.)
• Weekend-aware — Kedah/Kelantan/Terengganu use Fri-Sat (Kumpulan A), all others use Sat-Sun (Kumpulan B), with Johor's historical switch tracked
• Cuti ganti (replacement holiday) auto-calculation per state weekend config
• Business day calculator — per-state, holiday-aware
• School calendar — terms, holidays, KPM cuti perayaan (Lampiran A/B/C)
• Exam schedules — SPM, STPM, MUET, PT3
• iCal subscription feeds — per-state .ics feeds
• MCP Server for AI agents — 13 tools for Claude, ChatGPT, and other assistants
• TypeScript SDK (@catlabtech/mycal-sdk) with typed responses
• OpenAPI 3.1 spec + interactive docs
• Trilingual — Bahasa Melayu, English, Chinese names (三语支持)

Quick Start

# Clone and install
git clone https://github.com/Junhui20/malaysia-calendar-api.git
cd malaysia-calendar-api
pnpm install

# Build shared packages
pnpm --filter @catlabtech/mycal-core build
pnpm --filter @catlabtech/mycal-sdk build

# Run API locally (http://localhost:8787)
cd packages/api && npx wrangler dev

# Run web site locally (http://localhost:4321)
pnpm --filter @mycal/web dev

# Validate data
pnpm validate

# Run tests
pnpm test

API Examples

Base URL: https://mycal-api.huijun00100101.workers.dev/v1

List holidays

# All holidays for Selangor in 2026
curl "https://mycal-api.huijun00100101.workers.dev/v1/holidays?year=2026&state=selangor"

# Islamic holidays only
curl "https://mycal-api.huijun00100101.workers.dev/v1/holidays?year=2026&type=islamic"

# March holidays for KL
curl "https://mycal-api.huijun00100101.workers.dev/v1/holidays?year=2026&state=KL&month=3"

Check a date

# Is March 21 a holiday/weekend/working day?
curl "https://mycal-api.huijun00100101.workers.dev/v1/holidays/check?date=2026-03-21&state=KL"

Response:

{
  "data": {
    "date": "2026-03-21",
    "dayOfWeek": "Saturday",
    "isHoliday": true,
    "isWeekend": true,
    "isWorkingDay": false,
    "isSchoolDay": false,
    "holidays": [
      {
        "id": "2026-hari-raya-aidilfitri-1",
        "name": { "ms": "Hari Raya Aidilfitri", "en": "Eid al-Fitr", "zh": "开斋节" },
        "type": "islamic",
        "status": "confirmed"
      }
    ]
  }
}

Business days

# Count working days in March for Selangor
curl "https://mycal-api.huijun00100101.workers.dev/v1/business-days?start=2026-03-01&end=2026-03-31&state=selangor"

# Add 10 business days to a date
curl "https://mycal-api.huijun00100101.workers.dev/v1/business-days/add?date=2026-03-01&days=10&state=selangor"

School calendar

# Is this a school day?
curl "https://mycal-api.huijun00100101.workers.dev/v1/school/is-school-day?date=2026-03-21&state=selangor"

# School holidays for Kumpulan B
curl "https://mycal-api.huijun00100101.workers.dev/v1/school/holidays?year=2026&group=B"

# Exam schedule
curl "https://mycal-api.huijun00100101.workers.dev/v1/school/exams?year=2026&type=spm"

Next holiday

# Next holiday for Penang
curl "https://mycal-api.huijun00100101.workers.dev/v1/holidays/next?state=penang"

State resolution

# Resolve alias
curl "https://mycal-api.huijun00100101.workers.dev/v1/states/resolve?q=kl"
# -> { "data": { "canonical": "kuala-lumpur", "group": "B" } }

Full API Reference

Endpoint	Description
GET /v1/holidays	List holidays (filter by year, state, type, status, month)
GET /v1/holidays/check	Is this date a holiday/weekend/working day/school day?
GET /v1/holidays/today	Today's holiday status
GET /v1/holidays/next	Next upcoming holiday
GET /v1/holidays/between	Holidays in date range
GET /v1/holidays/leave-optimizer	Suggest annual-leave days to spend for the longest consecutive break
GET /v1/business-days	Count business days between dates
GET /v1/business-days/add	Add N business days to a date
GET /v1/states	All 16 states + 3 FTs with weekend config
GET /v1/states/resolve	Resolve alias (KL, penang, jb) to canonical code
GET /v1/school/terms	School term dates + day counts
GET /v1/school/holidays	School holidays + KPM cuti perayaan
GET /v1/school/exams	SPM, STPM, MUET, PT3 schedule
GET /v1/school/is-school-day	Is this a school day?
GET /v1/feed/ical/:state	iCal subscription feed
GET /v1/feed/csv/:state	CSV/spreadsheet export of holidays
GET /v1/data/*	Raw, cacheable open-data snapshots — manifest, states, holidays/:year, all (no API key required)
GET /v1/prayer-times/:zone	JAKIM prayer times for a zone (MYT-formatted); GET /v1/prayer-times/zones lists the zone directory
POST /v1/keys	Issue an API key (admin-gated for now; GET /v1/keys/whoami checks the caller's tier)

See the full OpenAPI 3.1 spec for request/response schemas.

SDK Usage

import { MyCalClient } from "@catlabtech/mycal-sdk";

const cal = new MyCalClient();

// Check if a date is a working day
const result = await cal.check("2026-03-21", "selangor");
console.log(result.isWorkingDay); // false

// List holidays
const holidays = await cal.holidays({ year: 2026, state: "KL" });

// Business days
const workDays = await cal.businessDays("2026-03-01", "2026-03-31", "selangor");
console.log(workDays.businessDays); // 22

// School calendar
const terms = await cal.school.terms({ year: 2026, group: "B" });
const exams = await cal.school.exams({ year: 2026, type: "spm" });
const isSchool = await cal.school.isSchoolDay("2026-03-21", "selangor");

MCP Server

Connect the Malaysia Calendar API to Claude, ChatGPT, or any MCP-compatible AI assistant.

Setup with Claude Desktop / Claude Code

Add to your MCP configuration:

{
  "mcpServers": {
    "malaysia-calendar": {
      "command": "npx",
      "args": ["@catlabtech/mycal-mcp-server"]
    }
  }
}

Available Tools (13)

Tool	Description
get_malaysia_holidays	Get public holidays (filter by year, state, type)
check_malaysia_holiday	Check if a date is a holiday or working day
next_malaysia_holiday	Find the next upcoming holiday
malaysia_business_days	Count working days between two dates
malaysia_long_weekends	Find long weekends (3+ days)
malaysia_leave_optimizer	Find the most efficient leave days to take to maximise consecutive days off
list_malaysia_states	List all states with weekend config
resolve_malaysia_state	Resolve alias (KL, JB) to canonical code
malaysia_holiday_changes	Recent data changes
malaysia_school_terms	School term dates and day counts
malaysia_school_holidays	School holidays (cuti penggal, cuti perayaan)
malaysia_exams	SPM, STPM, MUET, PT3 exam schedule
malaysia_is_school_day	Check if a date is a school day

State Codes

Code	Aliases	Group	Weekend
johor	jhr, jb	B	Sat-Sun (was Fri-Sat 2014-2024)
kedah	kd, kdh	A	Fri-Sat
kelantan	kel, kb	A	Fri-Sat
terengganu	trg, kt	A	Fri-Sat
perak	prk, ipoh	B	Sat-Sun
pulau-pinang	penang, pg	B	Sat-Sun
selangor	sel, sgr	B	Sat-Sun
negeri-sembilan	ns, n9	B	Sat-Sun
melaka	mlk, malacca	B	Sat-Sun
pahang	phg, kuantan	B	Sat-Sun
perlis	pls, kangar	B	Sat-Sun
sabah	sbh, kk	B	Sat-Sun
sarawak	swk, kuching	B	Sat-Sun
kuala-lumpur	kl	B	Sat-Sun
wp-putrajaya	putrajaya, pjy	B	Sat-Sun
wp-labuan	labuan, lbn	B	Sat-Sun

State aliases are case-insensitive. Use GET /v1/states/resolve?q=kl to resolve any alias to the canonical code.

Project Structure

malaysia-calendar-api/
├── data/                        # JSON data files (source of truth / 数据源)
│   ├── holidays/
│   │   ├── 2024.json            # Holiday data per year
│   │   ├── 2025.json
│   │   └── 2026.json
│   ├── school/
│   │   ├── terms-2026.json      # School terms (Kumpulan A + B)
│   │   ├── holidays-2026.json   # School holidays + KPM cuti perayaan
│   │   └── exams-2026.json      # SPM, STPM, MUET, PT3 schedules
│   ├── states.json              # 16 states + 3 FT, aliases, weekend history
│   └── known-fixed-holidays.json
├── packages/
│   ├── core/                    # Shared business logic (types, schemas, utils)
│   │   └── src/
│   │       ├── types.ts         # Holiday, State, SchoolTerm, Exam interfaces
│   │       ├── schemas.ts       # Zod validation schemas
│   │       ├── filter.ts        # Query filtering logic
│   │       ├── replacement.ts   # Cuti ganti calculation
│   │       ├── state-resolver.ts
│   │       ├── business-days.ts
│   │       └── school.ts        # School term/holiday/exam logic
│   ├── api/                     # Hono API on Cloudflare Workers
│   ├── mcp-server/              # MCP Server (13 tools)
│   ├── sdk/                     # TypeScript client SDK (@catlabtech/mycal-sdk)
│   └── web/                     # Astro + Starlight — marketing site, demos, docs
├── scripts/
│   ├── validate-data.ts         # 5-layer data validation pipeline
│   └── sync-to-kv.ts           # JSON -> Cloudflare KV denormalization
├── openapi.yaml                 # OpenAPI 3.1 spec (spec-first)
├── pnpm-workspace.yaml
└── turbo.json

Data Sources

All data is sourced from official Malaysian government publications:

Source	Data	URL
JPM BKPP	Federal Gazette / Warta Kerajaan (public holidays)	kabinet.gov.my
JAKIM	Takwim Hijri-Miladi (Islamic calendar)	e-solat.gov.my
KPM	Kalendar Akademik / school calendar (Lampiran A/B/C)	moe.gov.my
MPM	STPM & MUET exam schedules	mpm.edu.my
State Portals	State-specific holidays (16 states)	*.gov.my

Holiday data includes gazette references (e.g., P.U.(B) 305/2025) for traceability.

Deploy

Two parts deploy independently:

API → Cloudflare Workers

pnpm --filter @catlabtech/mycal-core build
cd packages/api && npx wrangler deploy

Website → Cloudflare Pages

pnpm --filter @catlabtech/mycal-core build
pnpm --filter @catlabtech/mycal-sdk build
pnpm --filter @mycal/web build

# Direct upload via wrangler (requires CLOUDFLARE_API_TOKEN + CLOUDFLARE_ACCOUNT_ID)
cd packages/web
npx wrangler pages deploy dist --project-name=mycal-web

First-time Pages setup:

1. Create a Pages project named mycal-web in the Cloudflare dashboard.
2. Either connect the GitHub repo for automatic builds, or rely on the GitHub Actions workflow (.github/workflows/deploy.yml) to push via wrangler pages deploy.
3. Required GitHub secrets: CLOUDFLARE_API_TOKEN, CLOUDFLARE_ACCOUNT_ID.

CI/CD

GitHub Actions handles:

1. PR gate — Zod schema validation + cross-source checks on every PR
2. Deploy — On merge to main: build and deploy API to Workers + Web to Pages in parallel
3. Daily scrape — Government portal monitoring for updates
4. Rukyah monitor — Islamic date confirmation tracking

Contributing

See CONTRIBUTING.md for how to:

• Report a missing holiday or cuti peristiwa
• Fix data errors
• Add new features

License

MIT