VS Code 1.142.0: Copilot chat's "Local" agent harness disappears; the picker only shows "Copilot" and "Cloud"

发生场景

Source(s): https://github.com/microsoft/vscode/issues/341937 Status: reported working by source, not reproduced by us (workaround only; root fix not confirmed).

问题

Local was the harness people used before, and a member of the VS Code organization on GitHub called it the most responsive. After the upgrade it cannot be picked, and restarting VS Code several times did not bring it back (original poster). A VS Code team member said chats created with Local are kept read-only and moved over automatically if you continue them.

报错原文（已脱敏/规范化）

Symptom (no error text): after upgrading to VS Code 1.142.0, the Copilot chat harness dropdown lists only "Copilot" and "Cloud"; the "Local" option is gone.

适用环境

VS Code 1.142.0, organizations with GitHub Copilot enterprise managed settings; reported 2026-10-16.

如何确认是这个问题

1. Open a new chat (not an old one) and open the harness picker → expect: only "Copilot" and "Cloud".
2. Ask your Copilot admin whether the enterprise managed settings set any permissions.* value or sandbox.enabled = true → expect: yes. The team member said VS Code 1.142 then disables Local on purpose so those policies stay enforced.

不是这个问题时 / 边界

Only an old chat lacks the option; a commenter said old chats keep the harness they were created with, so check a new chat first. Your organization does not manage Copilot settings at all; then the policy cause above does not apply, though step 2 may still bring Local back (our inference).

根因

The team member said that in 1.142, if an enterprise admin has set permissions.* or sandbox.enabled = true, VS Code forcibly disables Local in favor of the Copilot harness. The same release added a managed setting, temporaryDefaultToLocalHarness, that lets an admin keep Local during the move, at the cost of some reduced enforcement (team member). The release note link is in the thread.

占位变量

none.

修复步骤

1. Admin: set temporaryDefaultToLocalHarness to true in the organization's unified managed settings (a commenter's admins named it vscode.temporaryDefaultToLocalHarness, as in the release note) → expect: that commenter said Local was back for them after their admin configured it.
2. If your organization sets no such policy: add "chat.editor.localAgent.enabled": true, "chat.defaultToCopilotHarness": false and "chat.editor.preferCopilotHarness": false to your user settings.json, then start a new chat → expect: a commenter said the Local harness worked after this.

如何验证

Open a new chat → expect: "Local" is in the harness picker and a prompt runs on it.

试过没用的办法

Restarting VS Code several times did not help (original poster).

如何回滚

Remove the three lines from settings.json; the admin can set temporaryDefaultToLocalHarness back to false.

风险提示

If your admin set these policies, Local runs with less of that policy enforced (team member). Do not use step 2 or go back to an older VS Code to get around a permissions or sandbox policy your organization chose; ask the admin to use step 1 instead (our inference). The original poster got Local back by going back to the previous VS Code version, but that also drops the enforcement their admin set and misses later fixes (our inference). The team member described the managed setting as temporary, for the transition period.

验证范围

VS Code 1.142.0, October 2026.

何时失效

VS Code removes temporaryDefaultToLocalHarness or the Local harness. Open question: whether step 2 works on machines where an admin policy is in force; the commenter did not say whether their organization had one.