Redoc side menu - asp.net-core-3.1

Question

I want to use Redoc for my API documentation. I also have swagger.
I found here : https://github.com/Redocly/redoc this line - Integrate API Introduction into side menu - ReDoc takes advantage of markdown headings from OpenAPI description field. It pulls them into side menu and also supports deep linking.
I want to add my readme file to left side bar in Redoc. But I didn`t find any good example for it. What should I change, where readme should be added?
My redoc setup :
app.UseReDoc(c =>
{
c.DocumentTitle = $"Documentation";
c.SpecUrl = /api/docs/swagger.json";
c.RoutePrefix = "docs";
});

Answer 1

That documentation is referring to the info.description field.
You can embed the readme into the API definition like this:
info:
description:
$ref: ./path/to/readme.md
Replace that path with your actual path to the readme.
Source: https://redoc.ly/docs/api-reference-docs/embedded-markdown/#embedded-markdown-in-redocly-api-reference-docs
Note: If you are unable to change the API description, you could do it in post-processing using OpenAPI CLI and a custom decorator with the bundle command.