Instrument

Instrument — The Core Unit of Trading in Vyapari

The world of stock trading offers a wide variety of tradable instruments —
Common Stocks, Index Futures, Stock Futures, Options, Currency Pairs, and Commodities.

Vyapari lets you trade any of these instruments, across any Exchange supported by your Dalal.

What Is an Instrument?

The term Instrument appears throughout Vyapari — and for good reason.
You’ll work with Instruments directly, whether you’re backtesting, scanning, or trading live.

An Instrument in Vyapari represents a single tradable entity on a specific Stock Exchange.

For example:
A company like TCS trades on both NSE (Cash) and BSE (Cash).
Vyapari treats these as two separate Instruments, since they belong to different Exchanges and have independent data streams.

  • TCS @ NSE ≠ TCS @ BSE

Each Instrument is fully aware of its Exchange, trading session, and pricing details.

Instruments and Watchlists

In Vyapari, you can organize Instruments into collections called Watchlists.

The Back & Forward Test Engine and the Trade Engine both operate on such Watchlists — referring to them collectively as their Universe.

Tip "Quick Recap"

- A **Watchlist** is a user-defined collection of Instruments.  
- The **Universe** is the active Watchlist used by the Trade or Test Engine.  
- Each Instrument knows exactly which **Exchange** it belongs to.

Instrument Data Points

Every Instrument in Vyapari has a defined set of data fields.
Here are the key ones:

Property Description
Exchange The Stock Exchange where the Instrument is listed and traded.
Trading Symbol A unique string identifying the Instrument on its Exchange (e.g., TCS, NIFTY, BANKNIFTY).
Token A unique numeric ID used internally by Vyapari and the Dalal. You’ll never need to interact with it.
Instrument Type Classifies the Instrument as one of: Stock, Stock Future, Stock Option, Index, Index Future, Index Option, Currency Future, Currency Option, Commodity Future, or Commodity Option.
Derivative Type Describes whether the Instrument is a Future, Call Option, Put Option, or Not a Derivative.
Expiry Date Applicable only to Derivative Instruments (Futures & Options).
Strike Price Applicable only to Options.
Lot Size Defines the number of underlying units per derivative contract.
Tick Size The minimum price movement unit, e.g., ₹0.05 (5 paise) for most stocks.

What You Need to Know

As a Vyapari user, you only need to be familiar with a few key attributes:

  • Exchange
  • Trading Symbol
  • Instrument Type
  • Derivative Type
  • Expiry Date (for Derivatives)

All other details — like Token, Lot Size, and Tick Size — are handled automatically by Vyapari behind the scenes.

Note "Behind the Curtain"

Internal data fields help Vyapari:
- Manage trades accurately across multiple Exchanges  
- Sync live data from the Dalal
- Execute orders with precision in the Trade Engine

Summary

  • An Instrument is the smallest tradable entity in Vyapari.
  • Each Instrument is tied to a specific Exchange.
  • Instruments are grouped into Watchlists, which serve as Universes for trading and testing.
  • You only need to know a few fields — Vyapari handles the rest.

In essence, Instruments are the building blocks of Vyapari’s trading world —
everything you do begins and ends with them.