Session ses_301e1272

This is a Windows-side troubleshooting issue — nothing to explore in the codebase. Let me ask some clarifying questions to narrow down the problem.

That narrows it down perfectly. The issue is:

WezTerm's built-in SSH uses libssh2, NOT ssh.exe. When you use an SSH domain (wezterm connect), WezTerm uses its own embedded libssh2 library to connect. libssh2 has its own SSH agent support but on Windows it needs to talk to the \\.\pipe\openssh-ssh-agent named pipe — and it may not do this automatically depending on the WezTerm version/config.

Zed works because it shells out to ssh.exe, which picks up the Windows agent pipe natively.

The fix is to either:

1. Configure WezTerm to use the SSH agent pipe explicitly in its SSH domain config, or
2. Switch WezTerm to use ssh.exe as the backend instead of libssh2 (via ssh_backend = "Ssh2" → "LibSsh" naming is confusing — WezTerm actually has a "Ssh" backend that uses the system's ssh.exe)

This is entirely a WezTerm config issue on your Windows machine — nothing to change on the labs machine. Let me write up the troubleshooting plan:

The simplest fix — add one line to your wezterm.lua:

config.ssh_backend = "Ssh"

This switches WezTerm from its built-in libssh2 to spawning your system's ssh.exe for SSH connections. Since ssh.exe already works with Bitwarden's agent (that's how Zed connects), this should fix it immediately.

There's the problem — WezTerm is setting SSH_AUTH_SOCK to its own internal agent socket (wezterm/agent.20648), which overrides the Bitwarden pipe. That WezTerm agent socket doesn't exist or isn't working, so ssh-add -L fails.

Two options to fix this:

Option A: Override SSH_AUTH_SOCK in your WezTerm config to point to Bitwarden's pipe:

config.default_prog = { "powershell", "-NoLogo" }  -- or whatever your shell is
config.set_environment_variables = {
  SSH_AUTH_SOCK = "\\\\.\\pipe\\openssh-ssh-agent",
}

Option B: Disable WezTerm's built-in SSH agent so it stops overriding SSH_AUTH_SOCK:

config.mux_enable_ssh_agent = false

Option B is cleaner — it tells WezTerm to stop injecting its own agent, so ssh.exe inside WezTerm tabs will fall through to the Windows named pipe where Bitwarden is listening.

That wezterm cli --proxy flash suggests WezTerm is using its built-in mux/SSH domain path, not a plain ssh.exe call. The ssh_backend = "Ssh" setting may not apply to SSH domains the way we expected.

Let me ask a key question:

The wezterm cli --proxy flash means WezTerm is using its SSH domain path — it connects via libssh2 internally and then proxies the mux protocol over it. The ssh_backend and SSH_AUTH_SOCK settings don't help here because WezTerm's mux proxy bypasses ssh.exe entirely.

The simplest fix: stop using WezTerm's SSH domain and just ssh manually in a local tab instead.

Try this right now — open WezTerm so it gives you a local shell (PowerShell/cmd), then type:

ssh byk@100.102.146.109

Does Bitwarden prompt for fingerprint and connect?

If WezTerm auto-connects to the remote machine on launch (no local shell), then your wezterm.lua has either default_domain set to an SSH domain or a startup command that connects automatically. You'd need to remove/change that so WezTerm opens a local shell first.

Can you share what happens when you try the manual ssh approach in a local WezTerm tab?

WezTerm's SSH domains use libssh2 which should support the Windows named pipe agent. The issue is likely that WezTerm's own mux_enable_ssh_agent is intercepting before Bitwarden's pipe gets used. Let me check the WezTerm docs for the right config:

Docs moved to wezterm.org:

Now I have the full picture from the docs. Here are the key findings and the relevant pages for you to check:

Key docs pages:

• SshDomain: https://wezterm.org/config/lua/SshDomain.html
• ssh_backend: https://wezterm.org/config/lua/config/ssh_backend.html
• default_ssh_auth_sock: https://wezterm.org/config/lua/config/default_ssh_auth_sock.html
• mux_enable_ssh_agent: https://wezterm.org/config/lua/config/mux_enable_ssh_agent.html

Here's what the docs reveal:

1. ssh_backend has two values: "Ssh2" (libssh2) and "LibSsh" (libssh) — neither means "use system ssh.exe". Both are embedded SSH libraries. My earlier "Ssh" suggestion was wrong.

2. no_agent_auth on SshDomain — set to false (default) to allow agent auth. This should already be working.

3. default_ssh_auth_sock — this is the key one! It's a nightly-only feature that lets you override the SSH_AUTH_SOCK that WezTerm uses internally. On Windows, you'd point it at the Bitwarden pipe.

The real fix for your SSH domain is to add this to your wezterm.lua:

config.default_ssh_auth_sock = "\\\\.\\pipe\\openssh-ssh-agent"

This tells WezTerm's internal SSH library (libssh) to use the Bitwarden agent pipe instead of its own built-in agent. Combined with mux_enable_ssh_agent = false to stop WezTerm from overriding with its own agent.

However, default_ssh_auth_sock is marked as nightly-only. Are you on a nightly build of WezTerm, or a stable release? If stable, the fallback would be the ssh_option approach on the domain with identityagent.

I see the problem — your default_domain = 'WSL:Ubuntu'. WezTerm starts in WSL, and the SSH domain connection also goes through the mux server which runs in the WSL context. WSL doesn't have access to the Windows named pipe \\.\pipe\openssh-ssh-agent — that's a Windows-only construct.

The SSH connection from the SSH domain is made by the WezTerm process itself (which runs on Windows), not from inside WSL. But default_ssh_auth_sock with the Windows pipe path might not be getting applied correctly in this mixed WSL/Windows context.

A few things to try:

1. Check if no_agent_auth is accidentally true — your domain doesn't set it, so it should default to false (agent auth enabled). Good.

2. The real issue might be that WezTerm's libssh SSH backend on Windows doesn't know how to talk to the Windows named pipe for agent auth. The default_ssh_auth_sock feature is nightly-only and may not work with named pipes on Windows.

3. Try adding an explicit identityfile pointing to a key file as a workaround:

Since WezTerm's built-in SSH library may simply not support the Windows SSH agent pipe, you could export the private key from Bitwarden to a file and reference it directly:

ssh_domains = {
  {
    name = 'labs',
    remote_address = '100.69.65.125',
    username = 'byk',
    assume_shell = 'Posix',
    local_echo_threshold_ms = 10,
    connect_automatically = true,
    timeout = 300,
    ssh_option = {
      identityfile = 'C:\\Users\\BYK\\.ssh\\id_ed25519',
    },
  },
}

But that defeats the Bitwarden/fingerprint purpose.

4. The most likely working approach: use an ExecDomain that shells out to ssh.exe

This gives you the SSH domain UX (multiplexing, tabs) but uses ssh.exe which already works with Bitwarden:

ssh_domains = {},  -- remove the ssh_domain

exec_domains = {
  wezterm.exec_domain('labs', function(cmd)
    cmd.args = cmd.args or { 'bash', '-l' }
    local wrapped = {
      'ssh', 'byk@100.69.65.125', '-t', ...

That's a stable release from October 2025, not a nightly. The default_ssh_auth_sock config option is nightly-only per the docs — it's being silently ignored in your config.

So the core issue is: WezTerm's stable build has no way to tell its built-in SSH library (libssh) where to find the SSH agent on Windows.

Your options at this point:

1. Switch to a WezTerm nightly build — then default_ssh_auth_sock will actually work
2. Export the key to a file and use ssh_option = { identityfile = '...' } — works but loses the Bitwarden fingerprint gating
3. Use multiplexing = "None" on the SSH domain — this changes the connection mode and might use a different code path that respects the system agent

Before going further — can you try adding multiplexing = "None" to your SSH domain config? Like this:

ssh_domains = {
  {
    name = 'labs',
    remote_address = '100.69.65.125',
    username = 'byk',
    multiplexing = 'None',
    assume_shell = 'Posix',
    local_echo_threshold_ms = 10,
    connect_automatically = true,
    timeout = 300,
  },
}

With multiplexing = "None", WezTerm won't try to run wezterm cli --proxy on the remote side — it just does a plain SSH connection. This might use a code path that properly queries the Windows agent pipe. You lose mux features (can't split panes over the same connection) but it's worth testing to see if agent auth works at all.

If that doesn't work either, switching to a nightly is probably the way to go.

Download page with nightly builds: https://wezterm.org/installation.html

The Windows nightly should be at: https://wezterm.org/install/windows.html

Look for the "Nightly" section — there should be a direct .exe installer download link, or you can install via:

winget install wez.wezterm.nightly

That's a Windows security feature blocking access to the file through the symlink/junction. Try opening it with the full resolved path instead:

hx C:\Users\BYK\.wezterm.lua

Or if it's actually stored somewhere else and symlinked, find the real path:

Get-Item ~\.wezterm.lua | Select-Object -ExpandProperty Target

Let me re-read the default_ssh_auth_sock docs more carefully — it says it replaces SSH_AUTH_SOCK environment variable. But on Windows, the SSH agent pipe isn't accessed via SSH_AUTH_SOCK — that's a Unix concept. WezTerm's libssh on Windows might use a completely different mechanism to find the agent.

Let me check if there's a Windows-specific approach:

OK, I think the issue is that default_ssh_auth_sock sets SSH_AUTH_SOCK (a Unix environment variable), but WezTerm's libssh on Windows uses the Windows OpenSSH agent pipe via a completely different mechanism — it calls the Windows OpenSSH Authentication Agent service directly, not through an env var.

The mux_enable_ssh_agent docs confirm WezTerm manages its own agent symlink and SSH_AUTH_SOCK — it's a Unix-oriented feature.

I think WezTerm's libssh on Windows should automatically try the \\.\pipe\openssh-ssh-agent pipe (that's standard Windows OpenSSH behavior), and the fact that it's not working means either:

1. Bitwarden's pipe isn't actually at that standard path, or
2. WezTerm's libssh has a bug with Windows agent support

Can you run these two quick checks in PowerShell (not WSL):

# Check if the pipe exists
Get-ChildItem \\.\pipe\ | Where-Object { $_.Name -match 'ssh' }

# Try connecting manually  
ssh -v byk@100.69.65.125 2>&1 | Select-String -Pattern "agent|identity|auth"

This will tell us if the pipe is actually there and what ssh.exe sees when it connects.

Good — the pipe exists. So Bitwarden is correctly listening at \\.\pipe\openssh-ssh-agent.

The problem is likely that WezTerm's libssh library simply doesn't query the Windows named pipe for agent auth. It's a Linux-focused SSH library that uses SSH_AUTH_SOCK (Unix domain sockets), not Windows named pipes.

I think we've exhausted the WezTerm config options. The practical fix is to export the private key from Bitwarden to a file and point WezTerm's SSH domain at it directly:

1. In Bitwarden, open the SSH Key item → copy the private key
2. Save it to C:\Users\BYK\.ssh\id_ed25519_labs
3. Add to your WezTerm config:

ssh_domains = {
  {
    name = 'labs',
    remote_address = '100.69.65.125',
    username = 'byk',
    assume_shell = 'Posix',
    local_echo_threshold_ms = 10,
    connect_automatically = true,
    timeout = 300,
    ssh_option = {
      identityfile = 'C:\\Users\\BYK\\.ssh\\id_ed25519_labs',
    },
  },
}

You lose the fingerprint-per-connection gating for WezTerm specifically, but:

• The key file is still protected by Windows file permissions (only your user can read it)
• Zed still goes through Bitwarden's agent with fingerprint
• You can remove default_ssh_auth_sock since it's not doing anything

Not ideal, but WezTerm's SSH domain + Windows agent pipe is simply a gap in WezTerm's implementation.

That makes sense! The default ssh_backend = "LibSsh" (libssh) doesn't support the Windows agent pipe, but "Ssh2" (libssh2) does — libssh2 has native Windows named pipe agent support built in.

Glad you found it. You can also remove the default_ssh_auth_sock line now since it's not needed — libssh2 talks to \\.\pipe\openssh-ssh-agent automatically.