Agents Window SSH fails with Kerberos/GSSAPI authentication while Remote-SSH works

Does this issue occur when all extensions are disabled?: Yes / Not applicable

- VS Code Version: 1.138.0
- OS Version: macOS, Apple Silicon

Steps to Reproduce:

1. Connect to a remote Linux host using the standard VS Code Remote-SSH extension.
The host authenticates using Kerberos/GSSAPI, and the connection succeeds.

The system OpenSSH client also succeeds. Relevant debug output is:

Authentications that can continue: gssapi-keyex,gssapi-with-mic
Next authentication method: gssapi-with-mic
Authenticated ... using "gssapi-with-mic"

2. In the connected Remote-SSH VS Code window, confirm that:
- remote files work
- remote terminal works
- Copilot Chat works
- Codex works against the remote workspace

3. Open the dedicated Agents Window:

Chat: Open Agents Window

4. Create a new remote session:

New
-> Remote
-> SSH
-> select the same remote host

5. The Agents Window fails with:

All configured authentication methods failed

Expected behavior:

The Agents Window should be able to connect to the same remote host that standard Remote-SSH can already access successfully.

Ideally, one of the following should be supported:

1. Agents Window SSH supports Kerberos/GSSAPI authentication.

2. Agents Window can use the system OpenSSH client, similar to the Remote-SSH extension.

3. Preferably, the Agents Window can attach to or reuse an already-established Remote-SSH connection instead of starting a second independent SSH connection.

Actual behavior:

Standard Remote-SSH succeeds using system OpenSSH + Kerberos/GSSAPI, but the Agents Window fails with:

All configured authentication methods failed

Additional notes:

- This does not appear to be an SSH key / ssh-agent issue.
- `ssh-add -l` reports no identities, but system SSH still works because authentication is Kerberos/GSSAPI-based.
- Setting:

"remote.SSH.path": "/usr/bin/ssh"

affects normal Remote-SSH but does not change the Agents Window behavior.

- A custom SSH wrapper also works for standard Remote-SSH but does not affect the Agents Window connection.

Why this matters:

The dedicated Agents Window is important for multi-monitor remote-development workflows because it allows different agents to be used side by side while the main VS Code window remains focused on editing and terminals.
A typical workflow could be:
- Codex investigating a problem or planning a change.
- Claude implementing or rewriting code.
- Copilot reviewing the result, inspecting the codebase, or checking for issues.
These agents can be backed by different subscriptions or usage limits, so the Agents Window makes it practical to assign different parts of the work to different agents while they all operate on the same remote project.
For example:

Monitor 1:
VS Code Remote-SSH
editor + terminal

Monitor 2:
Agents Window
Codex / Copilot agents

Currently this workflow is blocked on Kerberos/GSSAPI-authenticated remote systems because the Agents Window cannot connect to the same remote host that standard Remote-SSH already accesses successfully.

Start by tracing the Agents Window path opened through “Chat: Open Agents Window” and “New → Remote → SSH”, then compare it with the standard Remote-SSH flow and its use of `remote.SSH.path`. Done means a Kerberos/GSSAPI-authenticated host connects from the Agents Window, with coverage for the reported authentication scenario.

Written by the indexing model from the issue text.