Integrate the Microsoft Outlook API.Caddi writes and runs the integration for you.
Microsoft Outlook has a REST API through Microsoft Graph. Self-serve for any developer who registers an Entra app, but mailbox access requires a Microsoft 365/Exchange Online or Outlook.com account and consent.
- 99%of agent runs complete successfully
- ~45 minon average to build your first agent
- 1M+back-office tasks completed
The connection is a project before it does anything.
Before the first record moves: an app registration, credentials, token refresh, and somewhere to host and monitor the code. 10,000 requests per 10 minutes, 4 concurrent requests, and 150 MB upload per 5 minutes per app per mailbox.
Register an app, store Microsoft Outlook credentials, refresh tokens and code around the rate limits.
Connect your Microsoft Outlook account once. Caddi holds the connection.
The job doesn't stop at Microsoft Outlook.
An intake, a filing or a client update also runs through email, documents and the other systems your team works in. The Microsoft Outlook API only reaches Microsoft Outlook.
Each extra system is another API, another set of credentials, another integration to own.
One automation runs across every tool the job touches, each through its API.
Someone has to own the code.
API versions change, fields get added and your process moves.
A developer patches and redeploys the integration each time.
The person who does the work updates it by showing or describing the change. Every automation is reviewed before it runs in production, and every run is logged.
What the Microsoft Outlook API gives you
- Type
- REST (JSON)
- Authentication
- OAuth 2.0 via Microsoft Entra ID (delegated or app-only)
- Who can get access
- Self-serve for any developer who registers an Entra app, but mailbox access requires a Microsoft 365/Exchange Online or Outlook.com account and consent.
- What it covers
- Messages, mail folders, rules, attachments, events, calendars, and categories.
- Limits
- 10,000 requests per 10 minutes, 4 concurrent requests, and 150 MB upload per 5 minutes per app per mailbox.
Official docs: learn.microsoft.com. Checked September 2026. Vendors change access terms, so confirm with Microsoft Outlook before you build.
When to build the Microsoft Outlook integration in-house
When you have engineers and the integration is your product, or you need one narrow sync between two systems and someone to own it. When the goal is getting Microsoft Outlook work off someone's desk, the build is the slow part, and Caddi does it for you.
What teams usually want the Microsoft Outlook API for
Claim Email Thread Triage
Caddi reviews the oldest claim email threads, identifies what follow-up is needed, and sends the next email — reducing manual thread triage for legal operations teams.
New Matter Setup
Caddi extracts client and matter details from new matter request emails, creates the client and matter workspace when needed, and files intake documents with the right attributes.
Cash Receipt Reconciliation
Caddi extracts invoice and payment details from cash receipt emails and writes them to the correct tracker row, reducing manual reconciliation work for billing and finance teams.
Meeting Invitation Emails
Caddi pulls verified client contact details to draft and send meeting invitation emails from a saved template and creates a follow-up task.
Everything Caddi does with Microsoft Outlook.
Microsoft Outlook API questions
Does Microsoft Outlook have an API?
Yes. Microsoft Outlook has a REST API through Microsoft Graph, authenticated with OAuth 2.0 via Microsoft Entra ID (delegated or app-only). The official documentation is at https://learn.microsoft.com/en-us/graph/outlook-mail-concept-overview.
How do I get access to the Microsoft Outlook API?
Self-serve for any developer who registers an Entra app, but mailbox access requires a Microsoft 365/Exchange Online or Outlook.com account and consent.
Does the Microsoft Outlook API have rate limits?
10,000 requests per 10 minutes, 4 concurrent requests, and 150 MB upload per 5 minutes per app per mailbox.
Can I connect Microsoft Outlook to my other tools without writing code against its API?
Yes. With Caddi you show the Microsoft Outlook task once, the way you'd train a new hire, and Caddi builds it as verified code that runs across Microsoft Outlook and the other tools the job touches. Steps that need a person's judgment are handed to Copilot or Claude, and Caddi monitors those too.
Do I need a developer to automate Microsoft Outlook with Caddi?
No. There is no integration code for you to write or maintain. Every automation Caddi builds for Microsoft Outlook is reviewed before it runs in production, and every run is logged.