Without prompting, king enters nude, as eccentric (7)

I believe the answer is:

unasked

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'without prompting' is the definition.
I can't tell whether this definition defines the answer.

'king enters nude as eccentric' is the wordplay.
'king' becomes 'K' (abbreviation for king in chess).
'enters' means one lot of letters goes inside another.
'eccentric' indicates anagramming the letters.
'nude'+'as'='nudeas'
'nudeas' anagrammed gives 'unased'.
'k' placed within 'unased' is 'UNASKED'.

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(Other definitions for unasked that I've seen before include "Without invitation" , "Gratuitous" , "(Done) voluntarily" , "Not invited" , "Without being bidden" .)

I've seen this clue in The Telegraph.

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