Improve documentation clarity for `tags` variable and update type in function definition.

[vonpetersenn]

Summary:

• Clarified the expected structure and content of the tags variable in the documentation.

Changes:

• Initially changed the type declaration of tags in the first commit, which caused errors in the test.
• Reverted the type declaration to maintain consistency with the library's style.

Notes:

• The type declaration was omitted to avoid test errors and adhere to the existing style of the library.

[ablaom]

@pebeto Do you have the possiblity to finish this review?

[pebeto]

LGTM.