Microsoft 365 MCP Server

reply-all-mail-message

reply-all-mail-message

Destructive

Reply to all recipients of a Microsoft 365 email using JSON or MIME, preserving HTML and saving the sent message to Sent Items.

Instructions

Reply to all recipients of a message using either JSON or MIME format. When using JSON format:

Specify either a comment or the body property of the message parameter. Specifying both will return an HTTP 400 Bad Request error.
If the original message specifies a recipient in the replyTo property, per Internet Message Format (RFC 2822), send the reply to the recipients in replyTo and not the recipient in the from property. When using MIME format:
Provide the applicable Internet message headers and the MIME content, all encoded in base64 format in the request body.
Add any attachments and S/MIME properties to the MIME content. This method saves the message in the Sent Items folder. Alternatively, create a draft to reply-all to a message and send it later.

💡 TIP: Reply-all preserving full HTML formatting. The 'comment' field is your reply text.

Input Schema

TableJSON Schema

Name	Required	Description
`body`	Yes
`confirm`	No	For destructive operations when the confirm gate is enabled (MS365_MCP_REQUIRE_CONFIRM=true; off by default). Set to true only after the user has explicitly approved this action. When the gate is on, calls without confirm: true return { error: "confirmation_required" } without touching user data.
`messageId`	Yes	Value for the 'messageId' path segment. Pass it under the name 'messageId', not as 'id'. Use the 'id' field of the message object as returned by Microsoft Graph.
`includeHeaders`	No	Include response headers (including ETag) in the response metadata
`excludeResponse`	No	Exclude the full response body and only return success or failure indication

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedv0.145.2Aug 22, 2026

removedInput schema / $defs

Removed value: -{
-  "def0": {
-    "additionalProperties": true,
-    "properties": {
-      "dateTime": {
-        "description": "A single point of time in a combined date and time representation ({date}T{time}; for example, 2017-08-29T04:00:00.0000000).",
-        "type": "string"
-      },
-      "timeZone": {
-        "description": "Represents a time zone, for example, 'Pacific Standard Time'. See below for more possible values.",
-        "type": [
-          "string",
-          "null"
-        ]
-      }
-    },
-    "type": "object"
-  },
-  "def1": {
-    "additionalProperties": true,
-    "properties": {
-      "emailAddress": {
-        "additionalProperties": true,
-        "properties": {
-          "address": {
-            "description": "The email address of the person or entity.",
-            "type": [
-              "string",
-              "null"
-            ]
-          },
-          "name": {
-            "description": "The display name of the person or entity.",
-            "type": [
-              "string",
-              "null"
-            ]
-          }
-        },
-        "type": "object"
-      }
-    },
-    "type": "object"
-  }
-}

changedInput schema / properties / body / properties / Message / anyOf

Previous value: -[
-  {
-    "additionalProperties": true,
-    "properties": {
-      "attachments": {
-        "description": "The fileAttachment and itemAttachment attachments for the message.",
-        "items": {
-          "additionalProperties": true,
-          "properties": {
-            "contentType": {
-              "description": "The MIME type.",
-              "type": [
-                "string",
-                "null"
-              ]
-            },
-            "id": {
-              "description": "The unique identifier for an entity. Read-only.",
-              "type": "string"
-            },
-            "isInline": {
-              "description": "true if the attachment is an inline attachment; otherwise, false.",
-              "type": "boolean"
-            },
-            "lastModifiedDateTime": {
-              "anyOf": [
-                {
-                  "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
-                  "format": "date-time",
-                  "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
-                  "type": "string"
-                },
-                {
-                  "type": "null"
-                }
-              ],
-              "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
-            },
-            "name": {
-              "description": "The attachment's file name.",
-              "type": [
-                "string",
-                "null"
-              ]
-            },
-            "size": {
-              "description": "The length of the attachment in bytes.",
-              "maximum": 2147483647,
-              "minimum": -2147483648,
-              "type": "number"
-            }
-          },
-          "type": "object"
-        },
-        "type": "array"
-      },
-      "bccRecipients": {
-        "description": "The Bcc: recipients for the message.",
-        "items": {
-          "$ref": "#/$defs/def1"
-        },
-        "type": "array"
-      },
-      "body": {
-        "additionalProperties": true,
-        "properties": {
-          "content": {
-            "description": "The content of the item.",
-            "type": [
-              "string",
-              "null"
-            ]
-          },
-          "contentType": {
-            "enum": [
-              "text",
-              "html"
-            ],
-            "type": "string"
-          }
-        },
-        "type": "object"
-      },
-      "bodyPreview": {
-        "description": "The first 255 characters of the message body. It is in text format.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "categories": {
-        "description": "The categories associated with the item",
-        "items": {
-          "type": [
-            "string",
-            "null"
-          ]
-        },
-        "type": "array"
-      },
-      "ccRecipients": {
-        "description": "The Cc: recipients for the message.",
-        "items": {
-          "$ref": "#/$defs/def1"
-        },
-        "type": "array"
-      },
-      "changeKey": {
-        "description": "Identifies the version of the item. Every time the item is changed, changeKey changes as well. This allows Exchange to apply changes to the correct version of the object. Read-only.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "conversationId": {
-        "description": "The ID of the conversation the email belongs to.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "conversationIndex": {
-        "description": "Indicates the position of the message within the conversation.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "createdDateTime": {
-        "anyOf": [
-          {
-            "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
-            "format": "date-time",
-            "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
-      },
-      "flag": {
-        "additionalProperties": true,
-        "properties": {
-          "completedDateTime": {
-            "$ref": "#/$defs/def0"
-          },
-          "dueDateTime": {
-            "$ref": "#/$defs/def0"
-          },
-          "flagStatus": {
-            "enum": [
-              "notFlagged",
-              "complete",
-              "flagged"
-            ],
-            "type": "string"
-          },
-          "startDateTime": {
-            "$ref": "#/$defs/def0"
-          }
-        },
-        "type": "object"
-      },
-      "from": {
-        "$ref": "#/$defs/def1"
-      },
-      "hasAttachments": {
-        "description": "Indicates whether the message has attachments. This property doesn't include inline attachments, so if a message contains only inline attachments, this property is false. To verify the existence of inline attachments, parse the body property to look for a src attribute, such as <IMG src='cid:image001.jpg@01D26CD8.6C05F070'>.",
-        "type": [
-          "boolean",
-          "null"
-        ]
-      },
-      "id": {
-        "description": "The unique identifier for an entity. Read-only.",
-        "type": "string"
-      },
-      "importance": {
-        "enum": [
-          "low",
-          "normal",
-          "high"
-        ],
-        "type": "string"
-      },
-      "inferenceClassification": {
-        "enum": [
-          "focused",
-          "other"
-        ],
-        "type": "string"
-      },
-      "internetMessageHeaders": {
-        "description": "A collection of message headers defined by RFC5322. The set includes message headers indicating the network path taken by a message from the sender to the recipient. It can also contain custom message headers that hold app data for the message.  Requires $select to retrieve. Read-only.",
-        "items": {
-          "additionalProperties": true,
-          "properties": {
-            "name": {
-              "description": "Represents the key in a key-value pair.",
-              "type": [
-                "string",
-                "null"
-              ]
-            },
-            "value": {
-              "description": "The value in a key-value pair.",
-              "type": [
-                "string",
-                "null"
-              ]
-            }
-          },
-          "type": "object"
-        },
-        "type": "array"
-      },
-      "internetMessageId": {
-        "description": "The message ID in the format specified by RFC2822.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "isDeliveryReceiptRequested": {
-        "description": "Indicates whether a read receipt is requested for the message.",
-        "type": [
-          "boolean",
-          "null"
-        ]
-      },
-      "isDraft": {
-        "description": "Indicates whether the message is a draft. A message is a draft if it hasn't been sent yet.",
-        "type": [
-          "boolean",
-          "null"
-        ]
-      },
-      "lastModifiedDateTime": {
-        "anyOf": [
-          {
-            "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
-            "format": "date-time",
-            "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
-      },
-      "multiValueExtendedProperties": {
-        "description": "The collection of multi-value extended properties defined for the message. Nullable.",
-        "items": {
-          "additionalProperties": true,
-          "properties": {
-            "id": {
-              "description": "The unique identifier for an entity. Read-only.",
-              "type": "string"
-            },
-            "value": {
-              "description": "A collection of property values.",
-              "items": {
-                "type": [
-                  "string",
-                  "null"
-                ]
-              },
-              "type": "array"
-            }
-          },
-          "type": "object"
-        },
-        "type": "array"
-      },
-      "singleValueExtendedProperties": {
-        "description": "The collection of single-value extended properties defined for the message. Nullable.",
-        "items": {
-          "additionalProperties": true,
-          "properties": {
-            "id": {
-              "description": "The unique identifier for an entity. Read-only.",
-              "type": "string"
-            },
-            "value": {
-              "description": "A property value.",
-              "type": [
-                "string",
-                "null"
-              ]
-            }
-          },
-          "type": "object"
-        },
-        "type": "array"
-      },
-      "subject": {
-        "description": "The subject of the message.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "toRecipients": {
-        "description": "The To: recipients for the message.",
-        "items": {
-          "$ref": "#/$defs/def1"
-        },
-        "type": "array"
-      }
-    },
-    "type": "object"
-  },
-  {
-    "additionalProperties": true,
-    "properties": {},
-    "type": "object"
-  }
-]New value: +[
+  {
+    "additionalProperties": true,
+    "properties": {
+      "attachments": {
+        "description": "The fileAttachment and itemAttachment attachments for the message.",
+        "items": {
+          "additionalProperties": true,
+          "properties": {
+            "contentType": {
+              "description": "The MIME type.",
+              "type": [
+                "string",
+                "null"
+              ]
+            },
+            "id": {
+              "description": "The unique identifier for an entity. Read-only.",
+              "type": "string"
+            },
+            "isInline": {
+              "description": "true if the attachment is an inline attachment; otherwise, false.",
+              "type": "boolean"
+            },
+            "lastModifiedDateTime": {
+              "anyOf": [
+                {
+                  "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
+                  "format": "date-time",
+                  "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
+                  "type": "string"
+                },
+                {
+                  "type": "null"
+                }
+              ],
+              "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
+            },
+            "name": {
+              "description": "The attachment's file name.",
+              "type": [
+                "string",
+                "null"
+              ]
+            },
+            "size": {
+              "description": "The length of the attachment in bytes.",
+              "maximum": 2147483647,
+              "minimum": -2147483648,
+              "type": "number"
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      },
+      "bccRecipients": {
+        "description": "The Bcc: recipients for the message.",
+        "items": {
+          "additionalProperties": true,
+          "properties": {
+            "emailAddress": {
+              "additionalProperties": true,
+              "properties": {
+                "address": {
+                  "description": "The email address of the person or entity.",
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                },
+                "name": {
+                  "description": "The display name of the person or entity.",
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                }
+              },
+              "type": "object"
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      },
+      "body": {
+        "additionalProperties": true,
+        "properties": {
+          "content": {
+            "description": "The content of the item.",
+            "type": [
+              "string",
+              "null"
+            ]
+          },
+          "contentType": {
+            "enum": [
+              "text",
+              "html"
+            ],
+            "type": "string"
+          }
+        },
+        "type": "object"
+      },
+      "bodyPreview": {
+        "description": "The first 255 characters of the message body. It is in text format.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "categories": {
+        "description": "The categories associated with the item",
+        "items": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "type": "array"
+      },
+      "ccRecipients": {
+        "description": "The Cc: recipients for the message.",
+        "items": {
+          "additionalProperties": true,
+          "properties": {
+            "emailAddress": {
+              "additionalProperties": true,
+              "properties": {
+                "address": {
+                  "description": "The email address of the person or entity.",
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                },
+                "name": {
+                  "description": "The display name of the person or entity.",
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                }
+              },
+              "type": "object"
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      },
+      "changeKey": {
+        "description": "Identifies the version of the item. Every time the item is changed, changeKey changes as well. This allows Exchange to apply changes to the correct version of the object. Read-only.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "conversationId": {
+        "description": "The ID of the conversation the email belongs to.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "conversationIndex": {
+        "description": "Indicates the position of the message within the conversation.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "createdDateTime": {
+        "anyOf": [
+          {
+            "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
+            "format": "date-time",
+            "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
+            "type": "string"
+          },
+          {
+            "type": "null"
+          }
+        ],
+        "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
+      },
+      "flag": {
+        "additionalProperties": true,
+        "properties": {
+          "completedDateTime": {
+            "additionalProperties": true,
+            "properties": {
+              "dateTime": {
+                "description": "A single point of time in a combined date and time representation ({date}T{time}; for example, 2017-08-29T04:00:00.0000000).",
+                "type": "string"
+              },
+              "timeZone": {
+                "description": "Represents a time zone, for example, 'Pacific Standard Time'. See below for more possible values.",
+                "type": [
+                  "string",
+                  "null"
+                ]
+              }
+            },
+            "type": "object"
+          },
+          "dueDateTime": {
+            "additionalProperties": true,
+            "properties": {
+              "dateTime": {
+                "description": "A single point of time in a combined date and time representation ({date}T{time}; for example, 2017-08-29T04:00:00.0000000).",
+                "type": "string"
+              },
+              "timeZone": {
+                "description": "Represents a time zone, for example, 'Pacific Standard Time'. See below for more possible values.",
+                "type": [
+                  "string",
+                  "null"
+                ]
+              }
+            },
+            "type": "object"
+          },
+          "flagStatus": {
+            "enum": [
+              "notFlagged",
+              "complete",
+              "flagged"
+            ],
+            "type": "string"
+          },
+          "startDateTime": {
+            "additionalProperties": true,
+            "properties": {
+              "dateTime": {
+                "description": "A single point of time in a combined date and time representation ({date}T{time}; for example, 2017-08-29T04:00:00.0000000).",
+                "type": "string"
+              },
+              "timeZone": {
+                "description": "Represents a time zone, for example, 'Pacific Standard Time'. See below for more possible values.",
+                "type": [
+                  "string",
+                  "null"
+                ]
+              }
+            },
+            "type": "object"
+          }
+        },
+        "type": "object"
+      },
+      "from": {
+        "additionalProperties": true,
+        "properties": {
+          "emailAddress": {
+            "additionalProperties": true,
+            "properties": {
+              "address": {
+                "description": "The email address of the person or entity.",
+                "type": [
+                  "string",
+                  "null"
+                ]
+              },
+              "name": {
+                "description": "The display name of the person or entity.",
+                "type": [
+                  "string",
+                  "null"
+                ]
+              }
+            },
+            "type": "object"
+          }
+        },
+        "type": "object"
+      },
+      "hasAttachments": {
+        "description": "Indicates whether the message has attachments. This property doesn't include inline attachments, so if a message contains only inline attachments, this property is false. To verify the existence of inline attachments, parse the body property to look for a src attribute, such as <IMG src='cid:image001.jpg@01D26CD8.6C05F070'>.",
+        "type": [
+          "boolean",
+          "null"
+        ]
+      },
+      "id": {
+        "description": "The unique identifier for an entity. Read-only.",
+        "type": "string"
+      },
+      "importance": {
+        "enum": [
+          "low",
+          "normal",
+          "high"
+        ],
+        "type": "string"
+      },
+      "inferenceClassification": {
+        "enum": [
+          "focused",
+          "other"
+        ],
+        "type": "string"
+      },
+      "internetMessageHeaders": {
+        "description": "A collection of message headers defined by RFC5322. The set includes message headers indicating the network path taken by a message from the sender to the recipient. It can also contain custom message headers that hold app data for the message.  Requires $select to retrieve. Read-only.",
+        "items": {
+          "additionalProperties": true,
+          "properties": {
+            "name": {
+              "description": "Represents the key in a key-value pair.",
+              "type": [
+                "string",
+                "null"
+              ]
+            },
+            "value": {
+              "description": "The value in a key-value pair.",
+              "type": [
+                "string",
+                "null"
+              ]
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      },
+      "internetMessageId": {
+        "description": "The message ID in the format specified by RFC2822.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "isDeliveryReceiptRequested": {
+        "description": "Indicates whether a read receipt is requested for the message.",
+        "type": [
+          "boolean",
+          "null"
+        ]
+      },
+      "isDraft": {
+        "description": "Indicates whether the message is a draft. A message is a draft if it hasn't been sent yet.",
+        "type": [
+          "boolean",
+          "null"
+        ]
+      },
+      "lastModifiedDateTime": {
+        "anyOf": [
+          {
+            "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
+            "format": "date-time",
+            "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
+            "type": "string"
+          },
+          {
+            "type": "null"
+          }
+        ],
+        "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
+      },
+      "multiValueExtendedProperties": {
+        "description": "The collection of multi-value extended properties defined for the message. Nullable.",
+        "items": {
+          "additionalProperties": true,
+          "properties": {
+            "id": {
+              "description": "The unique identifier for an entity. Read-only.",
+              "type": "string"
+            },
+            "value": {
+              "description": "A collection of property values.",
+              "items": {
+                "type": [
+                  "string",
+                  "null"
+                ]
+              },
+              "type": "array"
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      },
+      "singleValueExtendedProperties": {
+        "description": "The collection of single-value extended properties defined for the message. Nullable.",
+        "items": {
+          "additionalProperties": true,
+          "properties": {
+            "id": {
+              "description": "The unique identifier for an entity. Read-only.",
+              "type": "string"
+            },
+            "value": {
+              "description": "A property value.",
+              "type": [
+                "string",
+                "null"
+              ]
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      },
+      "subject": {
+        "description": "The subject of the message.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "toRecipients": {
+        "description": "The To: recipients for the message.",
+        "items": {
+          "additionalProperties": true,
+          "properties": {
+            "emailAddress": {
+              "additionalProperties": true,
+              "properties": {
+                "address": {
+                  "description": "The email address of the person or entity.",
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                },
+                "name": {
+                  "description": "The display name of the person or entity.",
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                }
+              },
+              "type": "object"
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      }
+    },
+    "type": "object"
+  },
+  {
+    "additionalProperties": true,
+    "properties": {},
+    "type": "object"
+  }
+]

Changed3 schema fields changedv0.134.4Jul 28, 2026

addedInput schema / $defs

Added value: +{
+  "def0": {
+    "additionalProperties": true,
+    "properties": {
+      "dateTime": {
+        "description": "A single point of time in a combined date and time representation ({date}T{time}; for example, 2017-08-29T04:00:00.0000000).",
+        "type": "string"
+      },
+      "timeZone": {
+        "description": "Represents a time zone, for example, 'Pacific Standard Time'. See below for more possible values.",
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  "def1": {
+    "additionalProperties": true,
+    "properties": {
+      "emailAddress": {
+        "additionalProperties": true,
+        "properties": {
+          "address": {
+            "description": "The email address of the person or entity.",
+            "type": [
+              "string",
+              "null"
+            ]
+          },
+          "name": {
+            "description": "The display name of the person or entity.",
+            "type": [
+              "string",
+              "null"
+            ]
+          }
+        },
+        "type": "object"
+      }
+    },
+    "type": "object"
+  }
+}

changedInput schema / properties / body / properties / Message / anyOf

Previous value: -[
-  {
-    "additionalProperties": true,
-    "properties": {
-      "attachments": {
-        "description": "The fileAttachment and itemAttachment attachments for the message.",
-        "items": {
-          "additionalProperties": true,
-          "properties": {
-            "contentType": {
-              "description": "The MIME type.",
-              "type": [
-                "string",
-                "null"
-              ]
-            },
-            "id": {
-              "description": "The unique identifier for an entity. Read-only.",
-              "type": "string"
-            },
-            "isInline": {
-              "description": "true if the attachment is an inline attachment; otherwise, false.",
-              "type": "boolean"
-            },
-            "lastModifiedDateTime": {
-              "anyOf": [
-                {
-                  "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
-                  "format": "date-time",
-                  "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
-                  "type": "string"
-                },
-                {
-                  "type": "null"
-                }
-              ],
-              "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
-            },
-            "name": {
-              "description": "The attachment's file name.",
-              "type": [
-                "string",
-                "null"
-              ]
-            },
-            "size": {
-              "description": "The length of the attachment in bytes.",
-              "maximum": 2147483647,
-              "minimum": -2147483648,
-              "type": "number"
-            }
-          },
-          "type": "object"
-        },
-        "type": "array"
-      },
-      "bccRecipients": {
-        "description": "The Bcc: recipients for the message.",
-        "items": {
-          "$ref": "#/properties/body/properties/Message/anyOf/0/properties/from"
-        },
-        "type": "array"
-      },
-      "body": {
-        "additionalProperties": true,
-        "properties": {
-          "content": {
-            "description": "The content of the item.",
-            "type": [
-              "string",
-              "null"
-            ]
-          },
-          "contentType": {
-            "enum": [
-              "text",
-              "html"
-            ],
-            "type": "string"
-          }
-        },
-        "type": "object"
-      },
-      "bodyPreview": {
-        "description": "The first 255 characters of the message body. It is in text format.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "categories": {
-        "description": "The categories associated with the item",
-        "items": {
-          "type": [
-            "string",
-            "null"
-          ]
-        },
-        "type": "array"
-      },
-      "ccRecipients": {
-        "description": "The Cc: recipients for the message.",
-        "items": {
-          "$ref": "#/properties/body/properties/Message/anyOf/0/properties/from"
-        },
-        "type": "array"
-      },
-      "changeKey": {
-        "description": "Identifies the version of the item. Every time the item is changed, changeKey changes as well. This allows Exchange to apply changes to the correct version of the object. Read-only.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "conversationId": {
-        "description": "The ID of the conversation the email belongs to.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "conversationIndex": {
-        "description": "Indicates the position of the message within the conversation.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "createdDateTime": {
-        "anyOf": [
-          {
-            "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
-            "format": "date-time",
-            "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
-      },
-      "flag": {
-        "additionalProperties": true,
-        "properties": {
-          "completedDateTime": {
-            "additionalProperties": true,
-            "properties": {
-              "dateTime": {
-                "description": "A single point of time in a combined date and time representation ({date}T{time}; for example, 2017-08-29T04:00:00.0000000).",
-                "type": "string"
-              },
-              "timeZone": {
-                "description": "Represents a time zone, for example, 'Pacific Standard Time'. See below for more possible values.",
-                "type": [
-                  "string",
-                  "null"
-                ]
-              }
-            },
-            "type": "object"
-          },
-          "dueDateTime": {
-            "$ref": "#/properties/body/properties/Message/anyOf/0/properties/flag/properties/completedDateTime"
-          },
-          "flagStatus": {
-            "enum": [
-              "notFlagged",
-              "complete",
-              "flagged"
-            ],
-            "type": "string"
-          },
-          "startDateTime": {
-            "$ref": "#/properties/body/properties/Message/anyOf/0/properties/flag/properties/completedDateTime"
-          }
-        },
-        "type": "object"
-      },
-      "from": {
-        "additionalProperties": true,
-        "properties": {
-          "emailAddress": {
-            "additionalProperties": true,
-            "properties": {
-              "address": {
-                "description": "The email address of the person or entity.",
-                "type": [
-                  "string",
-                  "null"
-                ]
-              },
-              "name": {
-                "description": "The display name of the person or entity.",
-                "type": [
-                  "string",
-                  "null"
-                ]
-              }
-            },
-            "type": "object"
-          }
-        },
-        "type": "object"
-      },
-      "hasAttachments": {
-        "description": "Indicates whether the message has attachments. This property doesn't include inline attachments, so if a message contains only inline attachments, this property is false. To verify the existence of inline attachments, parse the body property to look for a src attribute, such as <IMG src='cid:image001.jpg@01D26CD8.6C05F070'>.",
-        "type": [
-          "boolean",
-          "null"
-        ]
-      },
-      "id": {
-        "description": "The unique identifier for an entity. Read-only.",
-        "type": "string"
-      },
-      "importance": {
-        "enum": [
-          "low",
-          "normal",
-          "high"
-        ],
-        "type": "string"
-      },
-      "inferenceClassification": {
-        "enum": [
-          "focused",
-          "other"
-        ],
-        "type": "string"
-      },
-      "internetMessageHeaders": {
-        "description": "A collection of message headers defined by RFC5322. The set includes message headers indicating the network path taken by a message from the sender to the recipient. It can also contain custom message headers that hold app data for the message.  Requires $select to retrieve. Read-only.",
-        "items": {
-          "additionalProperties": true,
-          "properties": {
-            "name": {
-              "description": "Represents the key in a key-value pair.",
-              "type": [
-                "string",
-                "null"
-              ]
-            },
-            "value": {
-              "description": "The value in a key-value pair.",
-              "type": [
-                "string",
-                "null"
-              ]
-            }
-          },
-          "type": "object"
-        },
-        "type": "array"
-      },
-      "internetMessageId": {
-        "description": "The message ID in the format specified by RFC2822.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "isDeliveryReceiptRequested": {
-        "description": "Indicates whether a read receipt is requested for the message.",
-        "type": [
-          "boolean",
-          "null"
-        ]
-      },
-      "isDraft": {
-        "description": "Indicates whether the message is a draft. A message is a draft if it hasn't been sent yet.",
-        "type": [
-          "boolean",
-          "null"
-        ]
-      },
-      "lastModifiedDateTime": {
-        "anyOf": [
-          {
-            "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
-            "format": "date-time",
-            "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
-      },
-      "multiValueExtendedProperties": {
-        "description": "The collection of multi-value extended properties defined for the message. Nullable.",
-        "items": {
-          "additionalProperties": true,
-          "properties": {
-            "id": {
-              "description": "The unique identifier for an entity. Read-only.",
-              "type": "string"
-            },
-            "value": {
-              "description": "A collection of property values.",
-              "items": {
-                "type": [
-                  "string",
-                  "null"
-                ]
-              },
-              "type": "array"
-            }
-          },
-          "type": "object"
-        },
-        "type": "array"
-      },
-      "singleValueExtendedProperties": {
-        "description": "The collection of single-value extended properties defined for the message. Nullable.",
-        "items": {
-          "additionalProperties": true,
-          "properties": {
-            "id": {
-              "description": "The unique identifier for an entity. Read-only.",
-              "type": "string"
-            },
-            "value": {
-              "description": "A property value.",
-              "type": [
-                "string",
-                "null"
-              ]
-            }
-          },
-          "type": "object"
-        },
-        "type": "array"
-      },
-      "subject": {
-        "description": "The subject of the message.",
-        "type": [
-          "string",
-          "null"
-        ]
-      },
-      "toRecipients": {
-        "description": "The To: recipients for the message.",
-        "items": {
-          "$ref": "#/properties/body/properties/Message/anyOf/0/properties/from"
-        },
-        "type": "array"
-      }
-    },
-    "type": "object"
-  },
-  {
-    "additionalProperties": true,
-    "properties": {},
-    "type": "object"
-  }
-]New value: +[
+  {
+    "additionalProperties": true,
+    "properties": {
+      "attachments": {
+        "description": "The fileAttachment and itemAttachment attachments for the message.",
+        "items": {
+          "additionalProperties": true,
+          "properties": {
+            "contentType": {
+              "description": "The MIME type.",
+              "type": [
+                "string",
+                "null"
+              ]
+            },
+            "id": {
+              "description": "The unique identifier for an entity. Read-only.",
+              "type": "string"
+            },
+            "isInline": {
+              "description": "true if the attachment is an inline attachment; otherwise, false.",
+              "type": "boolean"
+            },
+            "lastModifiedDateTime": {
+              "anyOf": [
+                {
+                  "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
+                  "format": "date-time",
+                  "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
+                  "type": "string"
+                },
+                {
+                  "type": "null"
+                }
+              ],
+              "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
+            },
+            "name": {
+              "description": "The attachment's file name.",
+              "type": [
+                "string",
+                "null"
+              ]
+            },
+            "size": {
+              "description": "The length of the attachment in bytes.",
+              "maximum": 2147483647,
+              "minimum": -2147483648,
+              "type": "number"
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      },
+      "bccRecipients": {
+        "description": "The Bcc: recipients for the message.",
+        "items": {
+          "$ref": "#/$defs/def1"
+        },
+        "type": "array"
+      },
+      "body": {
+        "additionalProperties": true,
+        "properties": {
+          "content": {
+            "description": "The content of the item.",
+            "type": [
+              "string",
+              "null"
+            ]
+          },
+          "contentType": {
+            "enum": [
+              "text",
+              "html"
+            ],
+            "type": "string"
+          }
+        },
+        "type": "object"
+      },
+      "bodyPreview": {
+        "description": "The first 255 characters of the message body. It is in text format.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "categories": {
+        "description": "The categories associated with the item",
+        "items": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "type": "array"
+      },
+      "ccRecipients": {
+        "description": "The Cc: recipients for the message.",
+        "items": {
+          "$ref": "#/$defs/def1"
+        },
+        "type": "array"
+      },
+      "changeKey": {
+        "description": "Identifies the version of the item. Every time the item is changed, changeKey changes as well. This allows Exchange to apply changes to the correct version of the object. Read-only.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "conversationId": {
+        "description": "The ID of the conversation the email belongs to.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "conversationIndex": {
+        "description": "Indicates the position of the message within the conversation.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "createdDateTime": {
+        "anyOf": [
+          {
+            "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
+            "format": "date-time",
+            "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
+            "type": "string"
+          },
+          {
+            "type": "null"
+          }
+        ],
+        "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
+      },
+      "flag": {
+        "additionalProperties": true,
+        "properties": {
+          "completedDateTime": {
+            "$ref": "#/$defs/def0"
+          },
+          "dueDateTime": {
+            "$ref": "#/$defs/def0"
+          },
+          "flagStatus": {
+            "enum": [
+              "notFlagged",
+              "complete",
+              "flagged"
+            ],
+            "type": "string"
+          },
+          "startDateTime": {
+            "$ref": "#/$defs/def0"
+          }
+        },
+        "type": "object"
+      },
+      "from": {
+        "$ref": "#/$defs/def1"
+      },
+      "hasAttachments": {
+        "description": "Indicates whether the message has attachments. This property doesn't include inline attachments, so if a message contains only inline attachments, this property is false. To verify the existence of inline attachments, parse the body property to look for a src attribute, such as <IMG src='cid:image001.jpg@01D26CD8.6C05F070'>.",
+        "type": [
+          "boolean",
+          "null"
+        ]
+      },
+      "id": {
+        "description": "The unique identifier for an entity. Read-only.",
+        "type": "string"
+      },
+      "importance": {
+        "enum": [
+          "low",
+          "normal",
+          "high"
+        ],
+        "type": "string"
+      },
+      "inferenceClassification": {
+        "enum": [
+          "focused",
+          "other"
+        ],
+        "type": "string"
+      },
+      "internetMessageHeaders": {
+        "description": "A collection of message headers defined by RFC5322. The set includes message headers indicating the network path taken by a message from the sender to the recipient. It can also contain custom message headers that hold app data for the message.  Requires $select to retrieve. Read-only.",
+        "items": {
+          "additionalProperties": true,
+          "properties": {
+            "name": {
+              "description": "Represents the key in a key-value pair.",
+              "type": [
+                "string",
+                "null"
+              ]
+            },
+            "value": {
+              "description": "The value in a key-value pair.",
+              "type": [
+                "string",
+                "null"
+              ]
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      },
+      "internetMessageId": {
+        "description": "The message ID in the format specified by RFC2822.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "isDeliveryReceiptRequested": {
+        "description": "Indicates whether a read receipt is requested for the message.",
+        "type": [
+          "boolean",
+          "null"
+        ]
+      },
+      "isDraft": {
+        "description": "Indicates whether the message is a draft. A message is a draft if it hasn't been sent yet.",
+        "type": [
+          "boolean",
+          "null"
+        ]
+      },
+      "lastModifiedDateTime": {
+        "anyOf": [
+          {
+            "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z",
+            "format": "date-time",
+            "pattern": "^[0-9]{4,}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]([.][0-9]{1,12})?(Z|[+-][0-9][0-9]:[0-9][0-9])$",
+            "type": "string"
+          },
+          {
+            "type": "null"
+          }
+        ],
+        "description": "The Timestamp type represents date and time information using ISO 8601 format and is always in UTC time. For example, midnight UTC on Jan 1, 2014 is 2014-01-01T00:00:00Z"
+      },
+      "multiValueExtendedProperties": {
+        "description": "The collection of multi-value extended properties defined for the message. Nullable.",
+        "items": {
+          "additionalProperties": true,
+          "properties": {
+            "id": {
+              "description": "The unique identifier for an entity. Read-only.",
+              "type": "string"
+            },
+            "value": {
+              "description": "A collection of property values.",
+              "items": {
+                "type": [
+                  "string",
+                  "null"
+                ]
+              },
+              "type": "array"
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      },
+      "singleValueExtendedProperties": {
+        "description": "The collection of single-value extended properties defined for the message. Nullable.",
+        "items": {
+          "additionalProperties": true,
+          "properties": {
+            "id": {
+              "description": "The unique identifier for an entity. Read-only.",
+              "type": "string"
+            },
+            "value": {
+              "description": "A property value.",
+              "type": [
+                "string",
+                "null"
+              ]
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      },
+      "subject": {
+        "description": "The subject of the message.",
+        "type": [
+          "string",
+          "null"
+        ]
+      },
+      "toRecipients": {
+        "description": "The To: recipients for the message.",
+        "items": {
+          "$ref": "#/$defs/def1"
+        },
+        "type": "array"
+      }
+    },
+    "type": "object"
+  },
+  {
+    "additionalProperties": true,
+    "properties": {},
+    "type": "object"
+  }
+]

changedInput schema / properties / messageId / description

Previous value: -"Path parameter: messageId"New value: +"Value for the 'messageId' path segment. Pass it under the name 'messageId', not as 'id'. Use the 'id' field of the message object as returned by Microsoft Graph."

Changed1 schema field changedv0.131.2Jul 18, 2026
- changedInput schema / additionalProperties
```
Previous value: -falseNew value: +true
```

Changed1 schema field changedv0.131.1Jul 11, 2026

addedInput schema / properties / confirm

Added value: +{
+  "description": "For destructive operations when the confirm gate is enabled (MS365_MCP_REQUIRE_CONFIRM=true; off by default). Set to true only after the user has explicitly approved this action. When the gate is on, calls without confirm: true return { error: \"confirmation_required\" } without touching user data.",
+  "type": "boolean"
+}

Addedv0.114.0May 28, 2026
Removedv0.112.2May 22, 2026
Addedv0.110.0May 18, 2026
Removedv0.108.0May 15, 2026
Addedv0.96.0May 4, 2026

TDQS

A4.3/5.0

Behavior4/5

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

Annotations indicate destructiveHint=true and openWorldHint=true, but the description adds meaningful behavioral details: it mentions that specifying both comment and body results in HTTP 400, describes replyTo handling per RFC 2822, states that the message is saved in the Sent Items folder, and offers the draft alternative. It does not contradict annotations and provides beyond-annotation context about error conditions and delivery behavior.

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

Conciseness4/5

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

The description is structured with clear bullet points for JSON and MIME formats, and a tip at the end. It is moderately long but each section conveys necessary information about constraints and usage. The primary purpose is front-loaded, and the alternative draft approach is mentioned early. While it could be slightly trimmed, it remains well-organized and readable.

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?

Given the complexity (two formats, many possible message properties, no output schema), the description covers essential invocation details: required parameters (messageId, body), format-specific requirements, error conditions, and the saving behavior. It does not describe the response structure, but since there is no output schema and the tool returns a message object (per typical Graph API), the lack of explicit return documentation is acceptable. The description is sufficient for correct use.

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

Parameters4/5

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

The schema already covers 80% of parameters with descriptions (e.g., messageId, confirm, includeHeaders). The description adds critical semantics for the 'body' object by clarifying the mutually exclusive constraint between 'Comment' and 'Message' (body) and the replyTo precedence rule. For MIME format, it specifies base64 encoding and header/content requirements, going beyond the schema's generic object definition. This helps the agent avoid common mistakes (e.g., sending both fields).

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?

The description states a clear purpose: 'Reply to all recipients of a message using either JSON or MIME format.' This is specific (replies to all recipients, not just the sender), mentions two explicit format options, and distinguishes it from sibling tools like 'reply-mail-message' (which likely replies to a single recipient) through context. The name is also descriptive, but the description adds the format dimension and clarifies the scope (all recipients).

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?

The description provides practical usage guidance by contrasting with creating a draft: 'Alternatively, create a draft to reply-all to a message and send it later.' This gives an alternative for deferred sending. It also differentiates between JSON and MIME usage scenarios, including when to use 'comment' vs 'body'. However, it does not explicitly state when to use this tool over sibling 'reply-mail-message' (single reply) or 'reply-all' vs 'reply' distinctions, relying on the tool name for that differentiation.

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

Deploy Server

reply-all-mail-message

Instructions

Input Schema

Schema Changelog

TDQS

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