SSH client not attempting keys returned from 1Password agent

I have 2 computers, both running 1Password 8.9.8 on macOS 13 (Ventura). Both are logged into the same 1Password account and running the 1Password SSH agent. I have added the following 4 SSH keys to 1Password, which the agent reflects:

```
$ env | grep SSH

SSH_AUTH_SOCK=/Users/adam/.1password/agent.sock

$ ssh-add -l
256 SHA256:eum8cgSeUH7RHKAltGdQIIRoZN8ly4Dm40Q0oKQjFw0 (ED25519)
256 SHA256:NdEgj6UoJSWQrg82ueeHfWZxfzJmEAzbgUljZwQvShU (ED25519)
256 SHA256:wyCOVP0JcH6DP9VuYdGUR+NW1Urxa3KapWSpX+mJ544 (ED25519)
256 SHA256:mBCy6QPwWESMv3ugDluj7IMMmaMQ+iLO8vlPyeEL6PI (ED25519)
```

The second key SHA256:NdEgj6UoJSWQrg82ueeHfWZxfzJmEAzbgUljZwQvShU is attached to my GitHub account.

On the first computer, the 1Password SSH agent works as expected. It returns 5 keys (there's another one from a different Vault), SSH attempts each of these, and I'm able to connect:


$ ssh -v -T git@github.com
OpenSSH_9.0p1, LibreSSL 3.3.6
...
debug1: get_agent_identities: agent returned 5 keys
debug1: Will attempt key: /Users/adam.rothman/.ssh/id_ed25519 ED25519 SHA256:ECMfEhvQ50ija9WO4N1Ip64/Jxa46oojpfurc2ZItz0 agent
debug1: Will attempt key: <redacted> ED25519 SHA256:eum8cgSeUH7RHKAltGdQIIRoZN8ly4Dm40Q0oKQjFw0 agent
debug1: Will attempt key: <redacted> ED25519 SHA256:NdEgj6UoJSWQrg82ueeHfWZxfzJmEAzbgUljZwQvShU agent
debug1: Will attempt key: <redacted> ED25519 SHA256:wyCOVP0JcH6DP9VuYdGUR+NW1Urxa3KapWSpX+mJ544 agent
debug1: Will attempt key: <redacted> ED25519 SHA256:mBCy6QPwWESMv3ugDluj7IMMmaMQ+iLO8vlPyeEL6PI agent
debug1: Will attempt key: /Users/adam.rothman/.ssh/id_rsa
debug1: Will attempt key: /Users/adam.rothman/.ssh/id_ecdsa
debug1: Will attempt key: /Users/adam.rothman/.ssh/id_ecdsa_sk
debug1: Will attempt key: /Users/adam.rothman/.ssh/id_ed25519_sk
debug1: Will attempt key: /Users/adam.rothman/.ssh/id_xmss
debug1: Will attempt key: /Users/adam.rothman/.ssh/id_dsa
...
debug1: Offering public key: <redacted> ED25519 SHA256:NdEgj6UoJSWQrg82ueeHfWZxfzJmEAzbgUljZwQvShU agent
debug1: Server accepts key: <redacted> ED25519 SHA256:NdEgj6UoJSWQrg82ueeHfWZxfzJmEAzbgUljZwQvShU agent
Authenticated to github.com ([100.64.1.46]:22) using "publickey".
...
Hi adamrothman! You've successfully authenticated, but GitHub does not provide shell access.


On the second computer, the 1Password agent returns the 4 expected keys, but for reasons I don't understand, SSH does not attempting any of them:


$ ssh -v -T git@github.com
OpenSSH_9.0p1, LibreSSL 3.3.6
...
debug1: get_agent_identities: agent returned 4 keys
debug1: Will attempt key: /Users/adam/.ssh/id_rsa
debug1: Will attempt key: /Users/adam/.ssh/id_ecdsa
debug1: Will attempt key: /Users/adam/.ssh/id_ecdsa_sk
debug1: Will attempt key: /Users/adam/.ssh/id_ed25519
debug1: Will attempt key: /Users/adam/.ssh/id_ed25519_sk
debug1: Will attempt key: /Users/adam/.ssh/id_xmss
debug1: Will attempt key: /Users/adam/.ssh/id_dsa
...
debug1: No more authentication methods to try.
git@github.com: Permission denied (publickey).


The SSH configs on these 2 computers are not exactly the same, but I can't figure out what setting(s) might be preventing SSH from attempting the keys offered by the 1Password agent. This issue is not specific to github.com – it happens for all the SSH servers I've tried connecting to.

Thanks in advance for your help.

1Password Version: 8.9.8 (80908009)
Extension Version: N/A
OS Version: macOS Ventura 13.0.1 (22A400)
Browser:_ Chrome