> For the complete documentation index, see [llms.txt](https://docs.cartesi.io/llms.txt)

---
id: add-notice
title: "Add a new notice"
description: "The dApp backend can call this method to add a new notice when processing the advance-state request."
sidebar_label: "Add a new notice"
hide_title: true
hide_table_of_contents: true
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sidebar_class_name: "post api-method"
info_path: cartesi-rollups/_versioned_docs/version-1.5/rollups-apis/rollup/cartesi-rollup-http-api
custom_edit_url: null
---

import MethodEndpoint from "@theme/ApiExplorer/MethodEndpoint";
import ParamsDetails from "@theme/ParamsDetails";
import RequestSchema from "@theme/RequestSchema";
import StatusCodes from "@theme/StatusCodes";
import OperationTabs from "@theme/OperationTabs";
import TabItem from "@theme/TabItem";
import Heading from "@theme/Heading";

<Heading
  as={"h1"}
  className={"openapi__heading"}
  children={"Add a new notice"}
>
</Heading>

<MethodEndpoint
  method={"post"}
  path={"/notice"}
  context={"endpoint"}
>
  
</MethodEndpoint>



The dApp backend can call this method to add a new notice when processing the advance-state request.
A notice describes any changes to the internal state of the dApp that may be relevant to the blockchain.
Between calls to the finish method, the notice method can be called up to 32k times.

The returned value is the index of the notice for the current advance request.
In other words, the index counting restarts at every request.


<Heading
  id={"request"}
  as={"h2"}
  className={"openapi-tabs__heading"}
  children={"Request"}
>
</Heading>

<ParamsDetails
  parameters={undefined}
>
  
</ParamsDetails>

<RequestSchema
  title={"Body"}
  body={{"content":{"application/json":{"schema":{"type":"object","properties":{"payload":{"type":"string","description":"The payload is in the Ethereum hex binary format.\nThe first two characters are '0x' followed by pairs of hexadecimal numbers that correspond to one byte.\nFor instance, '0xdeadbeef' corresponds to a payload with length 4 and bytes 222, 173, 190, 175.\nAn empty payload is represented by the string '0x'.\n","example":"0xdeadbeef","title":"Payload"}},"title":"Notice"}}}}}
>
  
</RequestSchema>

<StatusCodes
  id={undefined}
  label={undefined}
  responses={{"200":{"description":"Created the notice.","content":{"application/json":{"schema":{"type":"object","properties":{"index":{"type":"integer","format":"uint64","description":"Position in the Merkle tree.","example":123}},"title":"IndexResponse"}}}},"default":{"description":"Error response.","content":{"text/plain":{"schema":{"type":"string","description":"Detailed error message.","example":"The request could not be understood by the server due to malformed syntax","title":"Error"}}}}}}
>
  
</StatusCodes>