The most common and most likely answer to this crossword clue is the 10 letter word BINOCULARS
I've seen this crossword clue in The Daily Telegraph
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More clues leading to the result BINOCULARS
Buddy explains!
The straight part
We know that "Best way to espy chirpy robin? Claus should deliver these" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case best way to espy chirpy robin? claus should deliver these = binoculars.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does BINOCULARS mean?
BINOCULARS noun- A hand-held device consisting of a series of lenses and prisms, used to magnify objects so that they can be better seen from a distance, and looked at through both eyes.