# Amazon Lex V2 API Reference
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This document provides detailed information about the Amazon Lex V2 API actions and their parameters.

For information about the IAM access control permissions you need to use this API, see [Identity-based policies for Amazon Lex](https://docs.aws.amazon.com/lexv2/latest/dg/security_iam_service-with-iam.html).

If you use a custom HTTP client to call Amazon Lex Model Building V2 operations, you must set the "Content-Type" HTTP header to "application/x-amz-json-1.1". Otherwise, you receive an HTTP 404 - UnknownOperationException in the response.

Amazon Lex Model Building V2 operations return the responses with the "application/x-amz-json-1.1" content type.

You can use [AWS SDKs](https://aws.amazon.com/tools/#sdk) to access Amazon Lex V2 APIs using your favorite programming language. The SDKs automatically perform useful tasks for you, such as:
+ Cryptographically sign your service requests
+ Retry requests
+ Handle error responses

The following resources provide additional information about the Amazon Lex V2 API.
+ *AWS General Reference*
  + [Amazon Lex V2 Endpoints for each region](https://docs.aws.amazon.com/general/latest/gr/lex.html).
+ *AWS Command Line Interface*
  + [ Amazon Lex Model Building V2 CLI commands](https://docs.aws.amazon.com/cli/latest/reference/lexv2-models/index.html).
  + [ Amazon Lex Runtime V2 CLI commands](https://docs.aws.amazon.com/cli/latest/reference/lexv2-runtime/index.html).

**Topics**
+ [Actions](API_Operations.md)
+ [Data Types](API_Types.md)
+ [Common Parameters](CommonParameters.md)
+ [Common Error Types](CommonErrors.md)