> This page is for version v1 API.
> For other versions, use one of these documentation indexes:
> - v2 API (default): https://docs.cohere.com/v2/llms.txt
> - v1 API: https://docs.cohere.com/v1/llms.txt

> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.cohere.com/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.cohere.com/_mcp/server.

# Versioning

> The document explains how to specify the API version using a URL in the header, defaulting to pre-2021-11-08 if no version is supplied. It also provides examples of how to specify the version in different programming languages and mentions the differences between stable and experimental versions.

You can specify the API version you want  to use by supplying a URL in the header. For example, the URL for the stable version of Generate would be `https://api.cohere.ai/v1/generate`.

If no version is supplied in the header, then the API will default to *no version*, meaning pre-`2021-11-08`. Important note that the SDKs will default you to the most recent version, which is currently `2022-12-06`.

## Other Methods

Previously, Cohere used very simple dated versioning in the format `YYYY-MM-DD`, not to be confused with our independent model-versioning. As of March 17, 2023, this versioning method is still available, but the URL method is preferred. All model versions are compatible with all API versions. The version must match absolutely to be applied, eg if `2022-12-06` is a version and you input `2022-12-07`, the API will return an error.

The version is supplied via a `Cohere-Version` header and is used as following;