# Data Structure Indexer API

The Data Structure Proofs API is a read-only API designed to help developers work with off-chain data structures used by Herodotus. Even though these data structures are kept off-chain, they have their roots committed on-chain. 

{% hint style="danger" %}
Most developers are unlikely to directly interact with this API, as its usage happens behind the scenes when interacting with the Storage Proof API.
{% endhint %}

Developers can query the Data Structure Indexer to retrieve:

* [Herodotus block hash accumulators](/herodotus-docs/protocol-design/historical-block-hash-accumulator.md)
* Individual block data within these accumulators
* Verifiable binary search path [linking a timestamp to a specific block numbers](/herodotus-docs/protocol-design/timestamp-to-block-number-mapper.md)
* List of timestamp remappers that Herodotus manages and indexes
* The peaks of a specific accumulator MMR
* MMR inclusion proofs for specific blocks

## Interactive Documentation

<https://rs-indexer.api.herodotus.cloud/swagger/>

<https://rs-indexer.api.herodotus.cloud/rapidoc/>

<https://rs-indexer.api.herodotus.cloud/redoc/>


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.herodotus.dev/herodotus-docs/developers/data-structure-indexer-api.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.