Intelligent beagle knew old criminal (13)

I believe the answer is:

knowledgeable

'intelligent' is the definition.
(thesaurus)

'beagle knew old criminal' is the wordplay.
'criminal' indicates anagramming the letters.
'beagle'+'knew'+'old'='beagleknewold'
'beagleknewold' is an anagram of 'KNOWLEDGEABLE'.

(Other definitions for knowledgeable that I've seen before include "Well informed" , "Erudite" , "Conversant" , "Intelligent and well-informed" , "Savvy" .)

I've seen this clue in The Telegraph.

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