> ## Documentation Index
> Fetch the complete documentation index at: https://docs.decibel.trade/llms.txt
> Use this file to discover all available pages before exploring further.

# On-Chain Reference

> Direct transaction reference for building on Decibel without the SDK

For developers who need to build transactions directly without using the TypeScript SDK, this section provides complete reference documentation for all on-chain operations.

<Note>
  Most developers should use the [TypeScript SDK](/typescript-sdk/overview) instead. The on-chain reference is for advanced use cases or when building in languages without SDK support.
</Note>

<Info>
  **Need the contract addresses?** See [Contract Addresses & Helpers](/developer-hub/on-chain/overview/contract-reference) for package addresses and common helper functions.
</Info>

## When to Use On-Chain Transactions

Building transactions directly (instead of using the SDK) is useful when:

* **Language support**: You're building in a language without an official SDK (e.g., Python, Go, Java)
* **Low-level control**: You need precise control over transaction construction
* **High-frequency trading**: You're optimizing for minimal latency
* **Custom integrations**: You're building infrastructure that requires direct blockchain interaction

## Transaction Categories

All Decibel transactions are executed on-chain on the Aptos blockchain through Move smart contract function calls.

<CardGroup cols={2}>
  <Card title="Account Management" icon="wallet" href="/developer-hub/on-chain/account-management/create-subaccount">
    Create Trading Accounts, deposit/withdraw collateral, delegate trading, and manage account settings
  </Card>

  <Card title="Order Management" icon="exchange" href="/developer-hub/on-chain/order-management/place-order">
    Place, cancel, and manage trading orders including limit, market, TWAP, and bulk orders
  </Card>

  <Card title="Position Management" icon="chart-line" href="/developer-hub/on-chain/position-management/place-tp-sl-order">
    Manage take-profit and stop-loss orders for positions
  </Card>

  <Card title="Builder Fee" icon="dollar-sign" href="/developer-hub/on-chain/builder-fee/approve-max-builder-fee">
    Approve and manage builder fees for Trading Accounts
  </Card>

  <Card title="Vault Operations" icon="vault" href="/developer-hub/on-chain/vault/create-and-fund">
    Create, fund, and manage trading vaults
  </Card>
</CardGroup>

## Getting Started

<Info>
  You'll need a [Node API token](/quickstart/node-api-key) to submit transactions to the Aptos fullnode, regardless of language.
</Info>

1. Get the [contract addresses and helper functions](/developer-hub/on-chain/overview/contract-reference)
2. Review [Optimized Transaction Building](/developer-hub/on-chain/overview/optimized-building) for performance best practices
3. Understand [price and size formatting](/developer-hub/on-chain/overview/formatting-prices-sizes) for order parameters
4. Explore the specific transaction type you need