B

Microsoft 365 MCP Server

MCP server for Microsoft 365 services via Graph API covering mail, calendar, files, contacts, tasks, OneNote, Teams, and Excel

Overall Score76/100

Score Breakdown

Server Info

Package
@softeria/ms-365-mcp-server
Registry
npm
Maintainer
Community
Category
Communication
Tags
emailcalendarteamssharepoint
Last Scanned
7 Apr 2026

Findings

7 issues

Authentication & Identity

LOWImplements MCP OAuth spec for per-user authentication

Full MCP OAuth spec implementation with .well-known/oauth-authorization-server and .well-known/oauth-protected-resource endpoints. Supports both stdio (device code flow via MSAL) and HTTP/StreamableHTTP transport with bearer token auth. Microsoft OAuth proxy pattern for authorization_code and refresh_token grants. Multi-account support with account parameter injection. Optional Azure Key Vault for secrets. Read-only mode supported via --readOnly flag.

Remediation

Document the required OAuth scopes for each tool.

Tool Schema Quality

HIGHRequired fields missing on 2 write operations

Write tools without required field declarations: login, logout.

Remediation

Add required arrays to all write/delete tool schemas.

MEDIUMOnly 0 of 8 schemas have parameter constraints

Most schemas lack maxLength, enum, or pattern constraints on string parameters.

Remediation

Add constraints to string parameters, especially on write operations.

CRITICALDangerous execution surface: execute-tool

Tool allows raw code/query execution which could be exploited via prompt injection.

Remediation

Use parameterized queries or validated command sets.

LLM Safety

MEDIUM5 tool descriptions are too vague

Short or generic descriptions make tool selection unreliable.

Remediation

Expand descriptions with specific actions, data types, and side effects.

HIGHTool descriptions contain instructional language

Descriptions include directives that could influence LLM behavior beyond tool selection.

Remediation

Remove instructional language. Descriptions should be purely factual.

Maintenance & Trust

LOWCommunity-maintained by Softeria

No official vendor backing.

Remediation

Seek vendor verification.

Tools

8 total
NameDescriptionRisk
loginAuthenticate with Microsoft using device code flowadmin
logoutLog out from Microsoft accountadmin
verify-loginCheck current Microsoft authentication statusread
list-accountsList all Microsoft accounts configured in this server.read
select-accountSelect a Microsoft account as the default.admin
remove-accountRemove a Microsoft account from the cache.admin
parse-teams-urlConverts any Teams meeting URL format into a standard joinWebUrl.read
[139 auto-generated Graph API tools]Tools auto-generated from Microsoft Graph API OpenAPI spec covering: list-mail-messages, send-mail, get-mail-message, create-event, list-events, list-files, create-todo-task, etc.write

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