| 401 on every call | API token incomplete or trimmed when copied | Re-copy the full token from vm.massedcompute.com/settings/api; don't edit it. |
| 401 then a browser login | Client is using MCP OAuth, not a pasted token | Expected. Finish sign-in and consent. Review the grant under Connected Apps. |
| Tool list missing destructive tools | Read-only key or read-only OAuth grant | Expected. Generate a full-scope API token, or reconnect the app and approve full access. |
| Client never shows an OAuth prompt | Token already in config, or old client | Remove the Authorization header if you want OAuth. Confirm the client supports HTTP MCP + OAuth. |
| 402 on launch | Billing not configured | Set recharge amount and threshold under Billing. |
| Cursor shows red MCP status | Cursor build older than 0.45 | Update Cursor; HTTP MCP requires 0.45+. |
| Image incompatible error | The chosen image doesn't match the chosen GPU | Pick a different image, or pick a different product. SXM-only images don't run on PCIe cards and vice versa. |
| Rate-limit (429) | Hitting our request limits | Wait a minute and try again. |