> For the complete documentation index, see [llms.txt](https://obytejs.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://obytejs.com/0.1.17/api/core.md).

# Core

- [Catchup](https://obytejs.com/0.1.17/api/core/catchup.md): Get balls units between 2 main chain ids.
- [Get hash tree](https://obytejs.com/0.1.17/api/core/get-hash-tree.md): Get units between balls.
- [Get light props](https://obytejs.com/0.1.17/api/core/get-light-props.md): Get light client properties.
- [Post joint](https://obytejs.com/0.1.17/api/core/post-joint.md): Post an unit on Byteball network.
- [Pick divisible coins for amount](https://obytejs.com/0.1.17/api/core/pick-divisible-coins-for-amount.md): Get spendable inputs from a specific amount and asset.
- [Heartbeat](https://obytejs.com/0.1.17/api/core/heartbeat.md): Send heartbeat to notify the node you are awake.