Workspace .mcp.json is never loaded in CLI 1.0.83 — 'mcp list' shows no Workspace group

Describe the bug

Copilot CLI 1.0.83 does not load workspace MCP config at all. A repo-root .mcp.json is ignored, and copilot mcp list never emits a Workspace group — only User servers:.

This is not a display-only problem: the servers are never started. The session log contains no spawn attempt for the workspace servers.

copilot mcp --help explicitly advertises the source:

Configuration is loaded from multiple sources:
  User       ~/.copilot/mcp-config.json
  Workspace  .mcp.json or .github/mcp.json
  Plugin     Installed plugins with MCP servers

Affected version

GitHub Copilot CLI 1.0.83.

macOS (Apple Silicon).

Steps to reproduce

In a pristine git repo, with no .vscode/ directory and no comments in the JSON:

mkdir repro && cd repro && git init -q .
cat > .mcp.json <<'JSON'
{
  "mcpServers": {
    "repro_probe": { "type": "local", "command": "node", "args": ["server.js"] }
  }
}
JSON
copilot mcp list
copilot mcp get repro_probe

Actual behavior

$ copilot mcp list
User servers:
  linear (http)
  figma (http)

$ copilot mcp get repro_probe
Error: Server "repro_probe" not found.

copilot mcp list --json likewise contains only "source": "user" entries — no workspace entries at all.

Expected behavior

repro_probe appears under a Workspace group and is started for the session.

Ruled out

Each of these was tested individually, not assumed:

Hypothesis	Result
Folder not trusted	Repo has an entry in ~/.copilot/permissions-config.json with write approvals
Version too old	1.0.83; support shipped in v0.0.401 per #1291
Enterprise/managed policy	Logs show managedSettings ... source=none, bypassDisabled=false
"type": "stdio" vs "local"	Both ignored
mcpServers vs servers key	Both ignored
.github/mcp.json path	Also ignored
Comments in JSON (#4323)	File is strict JSON, no comments; repro has no .vscode/mcp.json either
Not at repo root (#4765)	cwd is the repo root
Servers themselves broken	All start and authenticate fine when launched by hand, and work once copied into ~/.copilot/mcp-config.json

Possibly related

• #3126 — same end symptom (includeWorkspaceSources never set), but reported via the SDK's enableConfigDiscovery path. This report is the plain interactive CLI, so the two may share a root cause.
• #4542 — there mcp list does detect the workspace file and only the session connection fails; here it is never detected.
• #4636 — startup reconciliation dropping servers in 1.0.81-11, but for --additional-mcp-config.

Impact / workaround

Workspace .mcp.json is the only version-controlled way to share MCP servers with a team. The workaround is to duplicate every server into ~/.copilot/mcp-config.json using absolute paths, which is per-machine and not version-controlled, so each person repeats the setup and the lists drift.

Commencez par reproduire le problème avec le fichier .mcp.json à la racine du dépôt et comparez la découverte de l’espace de travail de la CLI interactive avec le chemin de configuration utilisateur. Suivez la raison pour laquelle la source Workspace est absente de copilot mcp list et confirmez qu’une configuration corrigée répertorie le serveur et le démarre pour une session.