PSA: My go-to method for spotting weak limbs before a climb
I always carry a cheap golf club in my kit to gently whack branches. If the wood gives a dull, soft feedback, it's probably compromised inside. A clean, sharp tap means it's solid and safe to put weight on. This little trick has helped avoid breakage while I'm up there.
Is this method actually reliable enough to trust with your safety? Even @clairem47 pointed out how eucalyptus can seem solid when it's not. In my experience, wood can sound fine but have hidden rot or cracks a simple tap won't find, so I wouldn't bet my weight on it alone.
Combine the sound check with a solid visual inspection every time, especially looking for fungus or weird soft spots you can poke with a knife. I still give limbs a good shake too, since some cracks only open up under a bit of movement. Eucalyptus is a total pain though, I get why people don't trust it lol.