MCP use JWT token authen failed g.user not found #41610

Bug description

I have successfuly start mcp and setup the mcp client via cline. which could fetcht eh mcp tools info as below successfully with the user's access_token. But when ask to execute the SQL have error response the g.user not found.

`Error: Error calling tool 'execute_sql': No authenticated user found. Tried:

• g.user was not set by JWT middleware (MCP_AUTH_ENABLED=True, JWT keys configured=True)
• MCP_DEV_USERNAME is not configured

Either pass a valid JWT bearer token or configure MCP_DEV_USERNAME for development.
2026-07-01 06:13:55,068:ERROR:superset.mcp_service.auth:MCP user resolution failed, denying request: No authenticated user found. Tried:

• g.user was not set by JWT middleware (MCP_AUTH_ENABLED=True, JWT keys configured=True)
• MCP_DEV_USERNAME is not configured

Either pass a valid JWT bearer token or configure MCP_DEV_USERNAME for development.
[07/01/26 06:13:55] Error calling tool 'execute_sql'
╭─────────── Traceback (most recent call last) ────────────╮
│ /usr/local/lib/python3.10/site-packages/fastmcp/server/s │
│ erver.py:1282 in call_tool │
│ │
│ /usr/local/lib/python3.10/site-packages/fastmcp/tools/ba │
│ se.py:392 in _run │
│ │
│ ... 2 frames hidden ... │
│ │
│ /usr/local/lib/python3.10/site-packages/superset/mcp_ser │
│ vice/auth.py:309 in _setup_user_context │
│ │
│ 306 │ │
│ 307 │ for attempt in range(2): │
│ 308 │ │ try: │
│ ❱ 309 │ │ │ user = get_user_from_request() │
│ 310 │ │ │ │
│ 311 │ │ │ # Validate user has necessary relation │
│ 312 │ │ │ # Force access to ensure they're loade │
│ │
│ /usr/local/lib/python3.10/site-packages/superset/mcp_ser │
│ vice/auth.py:213 in get_user_from_request │
│ │
│ 210 │ │ │ f"JWT keys configured={jwt_configured} │
│ 211 │ │ ) │
│ 212 │ │ details.append("MCP_DEV_USERNAME is not co │
│ ❱ 213 │ │ raise ValueError( │ │ 214 │ │ │ "No authenticated user found. Tried:\n │ │ 215 │ │ │ + "\n".join(f" - {d}" for d in detail │ │ 216 │ │ │ + "\n\nEither pass a valid JWT bearer │ ╰──────────────────────────────────────────────────────────╯ ValueError: No authenticated user found. Tried: - g.user was not set by JWT middleware (MCP_AUTH_ENABLED=True, JWT keys configured=True) - MCP_DEV_USERNAME is not configured Either pass a valid JWT bearer token or configure MCP_DEV_USERNAME for development. 2026-07-01 06:13:55,130:ERROR:superset.mcp_service.middleware:MCP tool error: tool=execute_sql, user_id=None, duration_ms=62, error_type=ToolError, error=Error calling tool 'execute_sql': No authenticated user found. Tried: - g.user was not set by JWT middleware (MCP_AUTH_ENABLED=True, JWT keys configured=True) - MCP_DEV_USERNAME is not configured Either pass a valid JWT bearer Token: [REDACTED] configure MCP_DEV_USERNAME for development. 2026-07-01 06:13:55,131:WARNING:superset.mcp_service.middleware:Failed to log error event: DBEventLogger.log() missing 3 required positional arguments: 'dashboard_id', 'slice_id', and 'referrer'
`

Mcp server was successfully started:

docker: entrypoint.sh script to start the mcp and superset
if [ "$SUPERSET_ENV" = "prod" ]; then
# Start superset worker for SQL Lab
celery --app=superset.tasks.celery_app:app worker -f /home/superset/log/celery_worker1.log -Ofair -nworker1 -c 4 -Q celery,thumbnails,reports &
celery --app=superset.tasks.celery_app:app worker -f /home/superset/log/celery_worker2.log -Ofair -nworker2 -c 4 -Q celery,thumbnails,reports &
celery --app=superset.tasks.celery_app:app beat -f /home/superset/log/celery_beat.log -s /home/superset/log/celerybeat-schedule &
celery --app=superset.tasks.celery_app:app flower --basic-auth=fadm:${FLOWER_PWD} &
superset mcp run --host 0.0.0.0 --port 5008 > /home/superset/log/mcp_server.log 2>&1 &
echo Started Celery workers[worker1, worker2] mcp server and Flower UI.

# Start the prod web server
gunicorn -w 10 -k gevent --timeout 600 -b  0.0.0.0:8088 --limit-request-line 0 --limit-request-field_size 0 "superset.app:create_app()"

026-07-01 06:11:34,339:INFO:httpx:HTTP Request: GET https://pypi.org/pypi/fastmcp/json "HTTP/1.1 200 OK"

╭──────────────────────────────────────────────────────────────────────────────╮
│ │
│ │
│ ▄▀▀ ▄▀█ █▀▀ ▀█▀ █▀▄▀█ █▀▀ █▀█ │
│ █▀ █▀█ ▄▄█ █ █ ▀ █ █▄▄ █▀▀ │
│ │
│ │
│ │
│ FastMCP 3.4.2 │
│ https://gofastmcp.com │
│ │
│ 🖥 Server: Mozart MCP Server, 3.4.2 │
│ 🚀 Deploy free: https://horizon.prefect.io │
│ │
╰──────────────────────────────────────────────────────────────────────────────╯

[07/01/26 06:11:34] INFO Starting MCP server 'Mozart MCP transport.py:304
Server' with transport
'streamable-http' (stateless) on
http://0.0.0.0:5008/mcp
INFO: Started server process [90]
INFO: Waiting for application startup.
2026-07-01 06:11:34,368:INFO:mcp.server.streamable_http_manager:StreamableHTTP session manager started
INFO: Application startup complete.
INFO: Uvicorn running on http://0.0.0.0:5008 (Press CTRL+C to quit)
"mcp_server.log" 477L, 44759C

Screenshots/recordings

mcp client connected successfully, but ask execute sql got g.user not found error

Superset version

6.1.0

Python version

3.10

Node version

16

Browser

Chrome

Additional context

No response

Checklist

• I have searched Superset docs and Slack and didn't find a solution to my problem.
• I have searched the GitHub issue tracker and didn't find a similar bug report.
• I have checked Superset's logs for errors and if I found a relevant Python stacktrace, I included it here as text in the "additional context" section.