Counteragents stationed all over the place (9)

I believe the answer is:

antidotes

I'm a little stuck... Click here to teach me more about this clue!

'counteragents' is the definition.
I can't judge whether this defines the answer.

'stationed all over the place' is the wordplay.
'all over the place' indicates an anagram.
'stationed' anagrammed gives 'ANTIDOTES'.

Can you help me to learn more?

(Other definitions for antidotes that I've seen before include "Counteractions to poisons" , "Remedies" , "Cures for poisons" .)

I've seen this clue in the Sydney Morning Herald.

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