Error when Git signing: Couldn't sign message (signer): communication with agent failed?

[danielcompton]

I've recently started using Secretive for signing Git commits with SSH and I occasionally get an error when signing like this:

$ git rebase master -i
error: Signing file /var/folders/d3/sd0zhwhj7pg3q596qc88hsnm0000gn/T//.git_signing_buffer_tmp3fOHCn
Couldn't sign message (signer): communication with agent failed?
Signing /var/folders/d3/sd0zhwhj7pg3q596qc88hsnm0000gn/T//.git_signing_buffer_tmp3fOHCn failed: communication with agent failed?

fatal: failed to write commit object
Could not apply 87dea7d545... WIP

I can reproduce it pretty reliably by rebasing a bunch of commits because Secretive is signing one after another. Retrying the commit works. Is there some more debugging info I can provide here?

I'm on a MacBook Pro M1 Max, macOS 15.1.1 (24B91).

[tommyknows]

I've started noticing the same thing, since upgrading to Sequoia. I'm not even sure if this is a Secretive issue, as I've seen other programs behave weirdly too... 🤔
Happy to provide some debug info as well.