Short answer
A tiny piece of cooked, plain clam meat is safe for a small kitten, but portion size is critical — think one pea-sized piece as a taste. For a cat this small, even a regular-sized clam can be too much due to the salt content and risk of digestive upset. Avoid tinned clams in brine entirely because of the high sodium. Watch for vomiting, diarrhea, or lethargy over the next day. It's safest to offer just a minimal taste and monitor closely, calling your vet if any concerns arise.
Clams — Food safety facts
Safe to share · Cats · full breakdown on the linked food page
Cooked clam meat is safe in small pieces. Watch the salt in tinned versions.
The full verdict, portion guidance and serving notes are collected on the Clams food facts page.