# Mintlify Index REST API

> Use the Mintlify Index REST API to search documentation and the web, assemble source-cited context, and retrieve page contents for applications and agents.

Use the Mintlify Index Representational State Transfer (REST) API to retrieve technical knowledge for applications and agents. The API supports three retrieval patterns:

- [`context`](/guides/api-search-index-context) assembles source-cited content within a token budget.
- [`search`](/guides/api-search-index-search) returns ranked documentation and web results.
- [`contents`](/guides/api-search-index-contents) retrieves content for selected Mintlify result IDs or result URLs.

:::callout{intent="info"}
The REST API requires an API key for your organization. The public [Index Model Context Protocol (MCP) server](/guides/search-index-mcp) does not require an API key.
:::

## Base URL

Send REST API requests to:

```text theme={null}
https://leaves.mintlify.com/api/universal-search/v1
```

Append an endpoint path to this base URL, for example `/context`, `/search`, or `/contents`.

## Authentication

Authenticate each request with an Index API key in the `Authorization` header:

```http theme={null}
Authorization: Bearer mint_us_...
```

Index API keys begin with `mint_us_`.

:::::steps
:::step{title="Create an Index API key"}
Open the [API keys page](https://app.mintlify.com/settings/organization/api-keys) in your dashboard and create an Index API key.
:::

::::step{title="Store the key securely"}
Save the key in a server-side environment variable. Mintlify only displays the complete key when you first create it. Store it securely.

```bash theme={null}
export MINTLIFY_INDEX_API_KEY="mint_us_..."
```

:::callout{intent="warning"}
Do not expose an Index API key in client-side code or commit it to version control.
:::
::::

:::step{title="Build context"}
Send your first request to the `context` endpoint:

```bash theme={null}
curl -X POST "https://leaves.mintlify.com/api/universal-search/v1/context" \
  -H "Authorization: Bearer $MINTLIFY_INDEX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "query": "How should I configure caching in Next.js 16?",
    "product": "Next.js",
    "format": "txt",
    "tokenBudget": 3000
  }'
```

A successful response includes assembled context with source URLs, the number of results used, and the output token count.
:::
:::::

## Rate limits

REST API limits apply per Mintlify organization. All API keys in an organization share the same limit:

| Window     |          Limit |
| ---------- | -------------: |
| Per second |    10 requests |
| Per day    | 1,000 requests |

Requests exceeding either limit return `429 Too Many Requests`. Use exponential backoff before retrying.

## Errors

| Status | Meaning                                       |
| ------ | --------------------------------------------- |
| `400`  | The request body is invalid.                  |
| `401`  | The API key is missing or invalid.            |
| `403`  | The request IP is not allowed by the API key. |
| `429`  | The organization exceeded a rate limit.       |
| `500`  | Index could not complete the request.         |

## Related topics

- [Mintlify REST API introduction](/docs/api/introduction.md)
- [llms.txt](/docs/ai/llmstxt.md)
- [Index](/docs/search-index/index.md)

## Related pages

- [Get result contents](./api-search-index-contents.md)
- [Build implementation context](./api-search-index-context.md)
- [Search technical knowledge](./api-search-index-search.md)

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