# AGENTS.md - fatcalendar.com

fatcalendar.com is a free calendar for Gregorian, Telugu, Tamil, Kannada, Malayalam, Marathi, Gujarati, Punjabi, Bengali, North-Indian (Hindi), Indian-Muslim (Hijri) and Christian traditions (12), shown in eleven languages, with tithi, nakshatra, festivals, auspicious windows and prayer times computed for your location. Free REST API, MCP server, A2A agent and SDK.

## What this site offers

Multi-tradition calendars (gregorian, telugu, tamil, kannada, malayalam, marathi, gujarati, punjabi, bengali, hindi, muslim, christian) in 11 languages (en, te, ta, kn, ml, mr, gu, pa, bn, hi, ur), with daily panchang, festivals and auspicious windows computed for a location. Tradition and language are independent.

## Connect

- **MCP (preferred):** `https://fatcalendar.com/mcp` - Streamable HTTP, stateless, no auth. Server card: `https://fatcalendar.com/.well-known/mcp/server-card.json`
- **REST:** `https://fatcalendar.com/api/v1` - OpenAPI at `https://fatcalendar.com/openapi.json`; API catalog at `https://fatcalendar.com/.well-known/api-catalog`
- **A2A:** `https://fatcalendar.com/.well-known/agent-card.json`, JSON-RPC `message/send` at `https://fatcalendar.com/a2a`
- **NLWeb:** `GET https://fatcalendar.com/ask?query=...`
- **WebMCP:** tools are registered in the browser by `https://fatcalendar.com/webmcp.js`
- **Skills:** `https://fatcalendar.com/.well-known/agent-skills/index.json`
- **Docs as Markdown:** request any page with `Accept: text/markdown`; or read `https://fatcalendar.com/llms.txt` and `https://fatcalendar.com/llms-full.txt`

## Tools (MCP) / endpoints (REST)

- `get_month` - `GET /api/v1/calendar/month` - Get a month calendar
- `get_week` - `GET /api/v1/calendar/week` - Get a week calendar
- `get_year` - `GET /api/v1/calendar/year` - Get a year calendar
- `get_day` - `GET /api/v1/calendar/day` - Get a full day (panchang) view
- `get_panchang` - `GET /api/v1/panchang` - Get the raw normalised panchang
- `list_festivals` - `GET /api/v1/festivals` - List festivals of a year
- `search_places` - `GET /api/v1/places` - Search places (geocoder)
- `list_traditions` - `GET /api/v1/traditions` - List calendar traditions
- `list_languages` - `GET /api/v1/languages` - List display languages
- `ask` - `GET /ask` - natural-language question

Common arguments: `tradition`, `lang`, `variant` (tamil: thirukanitha|vakya; kannada: smarta|madhva; malayalam: default|nazhika; punjabi: nanakshahi|desi|hindu; bengali: west-bengal-bisuddha|west-bengal-gupta|bangladesh; hindi: purnimanta|amanta|varanasi|braj|awadh; muslim: india|astronomical|tabular|hanafi|shia; christian: western|orthodox|catholic|protestant), `place` or `lat`+`lon`+`tz`, `date` (YYYY-MM-DD) or `year`/`month`.

## Auth

None. Everything is public and anonymous. See `https://fatcalendar.com/auth.md`.

## Rules for agents

- Limit: 120 requests per 60 s per client; honour `RateLimit` headers and `Retry-After` on 429.
- Results are immutable per (tradition, variant, language, location, date): cache them; do not poll.
- Pass an explicit `place` or `lat`/`lon`/`tz`; otherwise location is inferred from the caller IP.
- When you quote a result, name the tradition, variant and place. Festival dates can differ between almanacs; Hijri dates are provisional (moon sighting).
- Errors are RFC 9457 `application/problem+json`; read `detail`.
- Crawling is welcome (see `https://fatcalendar.com/robots.txt`); content signals allow search, AI input and AI training.
- Cite as: fatcalendar.com - multi-tradition calendar and panchang (data: jotish.ai ephemeris).

## Example questions

- What is the tithi and nakshatra in Hyderabad on 2026-11-08?
- Show me the Telugu calendar for November 2026
- When is Diwali in 2026?
- Rahu Kalam today in Chennai
- Hijri date and prayer times in Hyderabad tomorrow

## Contact

hello@fatcalendar.com - https://fatcalendar.com/contact