m365-mcp

Create Email Draft

email_create_draft

Creates an unsent email draft for review, returning its draft ID so you can send it later without sending anything now.

Instructions

Create an unsent email draft to review, then send later with email_send(mode='draft'). Sends nothing. Returns the draft ID.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`cc`	No	Cc recipients.
`to`	Yes	Recipients (To).
`bcc`	No	Bcc recipients.
`body`	Yes	Message body.
`subject`	Yes	Subject line.
`account_id`	No	Account ID or email address. Omit when only one account is signed in.
`importance`	No	Message importance.
`attachments`	No	Local files to attach: at most 10, each at most 25 MB.
`body_format`	No	Format of the body text you supply.	text

Output Schema

TableJSON Schema

Name	Required	Description
`cc`	Yes
`to`	Yes
`bcc`	Yes
`subject`	Yes
`summary`	Yes	One-line human summary. The tool's text content is this result serialized as JSON (summary included), so a client that ignores structuredContent still sees every field.
`draft_id`	Yes
`web_link`	Yes
`attachment_count`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed40 schema fields changedv1.0.0Sep 29, 2026

addedInput schema / $schema

Added value: +"https://json-schema.org/draft/2020-12/schema"

addedInput schema / additionalProperties
```
Added value: +false
```

addedInput schema / properties / account_id / description

Added value: +"Account ID or email address. Omit when only one account is signed in."

addedInput schema / properties / account_id / maxLength
```
Added value: +320
```
addedInput schema / properties / account_id / minLength
```
Added value: +1
```

removedInput schema / properties / attachments / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "items": {
-      "type": "string"
-    },
-    "type": "array"
-  },
-  {
-    "type": "null"
-  }
-]

removedInput schema / properties / attachments / default
```
Removed value: -null
```

addedInput schema / properties / attachments / description

Added value: +"Local files to attach: at most 10, each at most 25 MB."

addedInput schema / properties / attachments / items

Added value: +{
+  "description": "Local file path inside the server's allowed folders. Hidden and secret files are refused.",
+  "maxLength": 4096,
+  "minLength": 1,
+  "type": "string"
+}

addedInput schema / properties / attachments / maxItems
```
Added value: +10
```
addedInput schema / properties / attachments / type
```
Added value: +"array"
```
addedInput schema / properties / attachments / uniqueItems
```
Added value: +true
```

addedInput schema / properties / bcc

Added value: +{
+  "description": "Bcc recipients.",
+  "items": {
+    "description": "Email address, e.g. jane@example.com.",
+    "format": "email",
+    "maxLength": 320,
+    "minLength": 3,
+    "type": "string"
+  },
+  "maxItems": 500,
+  "type": "array",
+  "uniqueItems": true
+}

addedInput schema / properties / body / description
```
Added value: +"Message body."
```
addedInput schema / properties / body / maxLength
```
Added value: +1000000
```

addedInput schema / properties / body_format

Added value: +{
+  "default": "text",
+  "description": "Format of the body text you supply.",
+  "enum": [
+    "text",
+    "html"
+  ],
+  "type": "string"
+}

removedInput schema / properties / cc / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "items": {
-      "type": "string"
-    },
-    "type": "array"
-  },
-  {
-    "type": "null"
-  }
-]

removedInput schema / properties / cc / default
```
Removed value: -null
```
addedInput schema / properties / cc / description
```
Added value: +"Cc recipients."
```

addedInput schema / properties / cc / items

Added value: +{
+  "description": "Email address, e.g. jane@example.com.",
+  "format": "email",
+  "maxLength": 320,
+  "minLength": 3,
+  "type": "string"
+}

addedInput schema / properties / cc / maxItems
```
Added value: +500
```
addedInput schema / properties / cc / type
```
Added value: +"array"
```
addedInput schema / properties / cc / uniqueItems
```
Added value: +true
```

addedInput schema / properties / importance

Added value: +{
+  "description": "Message importance.",
+  "enum": [
+    "low",
+    "normal",
+    "high"
+  ],
+  "type": "string"
+}

addedInput schema / properties / subject / description
```
Added value: +"Subject line."
```
addedInput schema / properties / subject / maxLength
```
Added value: +998
```
addedInput schema / properties / subject / minLength
```
Added value: +1
```

removedInput schema / properties / to / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "items": {
-      "type": "string"
-    },
-    "type": "array"
-  }
-]

addedInput schema / properties / to / description
```
Added value: +"Recipients (To)."
```

addedInput schema / properties / to / items

Added value: +{
+  "description": "Email address, e.g. jane@example.com.",
+  "format": "email",
+  "maxLength": 320,
+  "minLength": 3,
+  "type": "string"
+}

addedInput schema / properties / to / maxItems
```
Added value: +500
```
addedInput schema / properties / to / minItems
```
Added value: +1
```
addedInput schema / properties / to / type
```
Added value: +"array"
```
addedInput schema / properties / to / uniqueItems
```
Added value: +true
```

changedInput schema / required

Previous value: -[
-  "account_id",
-  "to",
-  "subject",
-  "body"
-]New value: +[
+  "to",
+  "subject",
+  "body"
+]

addedOutput schema / $schema

Added value: +"https://json-schema.org/draft/2020-12/schema"

changedOutput schema / additionalProperties
```
Previous value: -trueNew value: +false
```
addedOutput schema / description
```
Added value: +"The created draft."
```

addedOutput schema / properties

Added value: +{
+  "attachment_count": {
+    "minimum": 0,
+    "type": "integer"
+  },
+  "bcc": {
+    "items": {
+      "type": "string"
+    },
+    "type": "array"
+  },
+  "cc": {
+    "items": {
+      "type": "string"
+    },
+    "type": "array"
+  },
+  "draft_id": {
+    "type": "string"
+  },
+  "subject": {
+    "type": "string"
+  },
+  "summary": {
+    "description": "One-line human summary. The tool's text content is this result serialized as JSON (summary included), so a client that ignores structuredContent still sees every field.",
+    "type": "string"
+  },
+  "to": {
+    "items": {
+      "type": "string"
+    },
+    "type": "array"
+  },
+  "web_link": {
+    "anyOf": [
+      {
+        "type": "string"
+      },
+      {
+        "type": "null"
+      }
+    ]
+  }
+}

addedOutput schema / required

Added value: +[
+  "draft_id",
+  "subject",
+  "to",
+  "cc",
+  "bcc",
+  "attachment_count",
+  "web_link",
+  "summary"
+]

First observedv0.2.3Jun 10, 2026

TDQS

A4.2/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations declare readOnlyHint=false and destructiveHint=false, so the write-but-non-destructive profile is partly covered. The description adds real value beyond them: 'Sends nothing' clarifies no mail is dispatched, and 'Returns the draft ID' signals the response shape. It stops short of noting the draft is idempotent-or-not or attachment/auth constraints.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three short, front-loaded sentences with zero filler. Each sentence carries distinct information: purpose, non-sending behavior, and the follow-up send path.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With 9 params fully documented in schema and an output schema present, the description does not need to explain fields or return values. It covers purpose, the send-nothing guarantee, and the handoff to email_send, which is sufficient for correct invocation; only minor edge contexts (account_id omission, attachment path rules) are left to the schema.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% across all 9 parameters, so the schema already documents to/cc/bcc/body/subject/account_id/importance/attachments/body_format fully. The description adds no parameter-level detail beyond that, so the baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource ('Create an unsent email draft') and immediately clarifies it sends nothing, distinguishing it from email_send. An agent can tell it apart from email_send and email_reply without opening any schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Names the alternative and the follow-up path explicitly ('then send later with email_send(mode="draft")'), which tells the agent this is the compose-and-review step. It gives clear use context but does not spell out when not to use it (e.g. sending directly).

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.