> For the complete documentation index, see [llms.txt](https://tokens-economy.gitbook.io/consensus/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://tokens-economy.gitbook.io/consensus/chain-based-proof-of-capacity-space/proof-of-believability.md).

# Proof of Believability

IOST introduced Servi as both a measurement of users’ contribution to the community and a way to encourage members to contribute to the continued development of the IOSChain.

#### Used in

* IOST

  **Read more**
* [whitepaper](https://github.com/iost-official/Documents/blob/master/Technical_White_Paper/EN/Tech_white_paper_EN.md#consensus-mechanism)