This is explained right here:

https://www.home-assistant.io/docs/configuration/secrets/#using-secretsyaml

../Frenck

This is explained right here:

No, it is literally NOT explained there. At least there is no clarifivation whether you need that !include thing or not.

I ask because when searching through the internet, I have found contradictory information about this.

Some people add this line to their configuration.yaml:
secrets: !include secrets.yaml
while others don't, and they explain that the above line should not be necessary.
So how comes that? I have tried with and without, and with it I get an error that secrets: (or secret:, I've tried both) is not an integration. So why some people do add it?

Has there been a change in how you use secrets? It should be clarified on the secrets documentaion page.

Well, that link provided by @frenck actually describes how to use it, I use it in the way as described in that link, and it works fine for over 2 years.

If the document would need to describe everything one can find on the internet that is either old or incorrect, it would be hardly readable.

I think you misunderstand me. My problem is this "old and incorrect" heap of information that can be found all over the internet.
I'm not demanding instructions for older HA versions, I'm demanding a sort of clarification that the line secrets: !include secrets.yaml IS NO LONGER NEEDED. Which is contrary to older information.

A question to ChatGPT solved my problem.
Maybe the HA developers want to include parts of it, just for clarification that the formerly used !include line is no longer needed and leads to an error.

In Home Assistant 2025.2 you no longer need to include the entry
secrets: !include secrets.yaml
in your configuration.yaml. Home Assistant automatically loads the secrets.yaml file, as long as it is located in the same directory as your configuration.yaml. This was necessary in older versions but has now become superfluous.
So if you already manage your secrets in a separate file and reference them in your configuration using !secret , you can safely omit that entry. This simplifies your configuration and avoids potential issues like double-loading or conflicts.
In short:
Previously: An explicit entry was often needed.
Now (2025.2): Automatic loading means the entry is no longer required.

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