Microsoft 365 (Microsoft Graph)
Unified REST API gateway to all Microsoft 365 services — read and send Outlook email, manage Teams channels and messages, access SharePoint files, query calendars, and interact with OneDrive.
Score Breakdown
⚙ Agent Friendliness
🔒 Security
Granular OAuth scopes with least-privilege support; Conditional Access policies can restrict agent app registrations; client secrets should be replaced with certificate credentials or managed identities for production use.
⚡ Reliability
Best When
Your agent operates within a Microsoft 365 enterprise environment and needs to read, write, or react to email, calendar, Teams, or SharePoint data.
Avoid When
Users are on Google Workspace or the integration only needs one narrow M365 capability that has a dedicated lighter-weight API.
Use Cases
- • Drafting and sending emails or meeting invites on behalf of users via Outlook Mail and Calendar APIs
- • Searching and summarizing documents from SharePoint and OneDrive for enterprise knowledge retrieval
- • Posting messages or creating Teams channels as part of automated notification or incident-response workflows
- • Reading and writing user profile and organizational directory data for identity-aware agent personalization
- • Subscribing to change notifications (webhooks) on mailboxes or calendars to trigger event-driven agent actions
Not For
- • Consumer Microsoft accounts without an M365 subscription — many Graph scopes require organizational tenants
- • Bulk data export or archival at scale — Graph throttling and pagination make it unsuitable for full-corpus data pipelines
- • Real-time Teams meeting audio/video processing — Graph does not expose media streams
Interface
Authentication
Azure AD / Entra ID OAuth 2.0 with granular permission scopes (e.g. Mail.Read, Calendars.ReadWrite); supports both delegated (user context) and application (daemon) permissions; admin consent required for many application-level scopes.
Pricing
No per-call API charges; access gated by M365 license held by the tenant and user; some advanced features (e.g. advanced eDiscovery) require higher SKUs.
Agent Metadata
Known Gotchas
- ⚠ Admin consent is required for application permissions — delegated flows need a human OAuth dance, which blocks fully headless agents
- ⚠ Throttling is tenant-wide per app registration, so a noisy background job can starve foreground agent calls — use separate app registrations
- ⚠ Change notification subscriptions expire (max 4230 minutes for most resources) and must be renewed proactively or webhooks silently stop firing
- ⚠ The $search query parameter uses KQL syntax and is only supported on specific resources (not all list endpoints support full-text search)
- ⚠ Beta endpoint (/beta) has useful features but breaking changes occur without versioned notice — never use /beta in production agents
Alternatives
Full Evaluation Report
Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for Microsoft 365 (Microsoft Graph).
Scores are editorial opinions as of 2026-03-06.