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send_conversation

Send messages to students through Canvas Conversations, with bulk options and a preview confirmation for multiple recipients.

Instructions

Send messages to students via Canvas conversations.

Sending to ONE recipient is a single call. Sending to MULTIPLE recipients is two-step: call without a confirmation_token to get a preview (recipients, subject, body) plus a token; show that preview to the educator, then call again with the token and identical arguments to actually send. The token expires, is single-use, and is void if any argument changed since the preview.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`body`	Yes	Message content
`mode`	No	"sync" or "async" (use async for >100 recipients)	sync
`subject`	Yes	Message subject (max 255 chars)
`force_new`	No	Force new conversation even if one exists
`bulk_message`	No	Send individual messages with same subject to each recipient
`context_code`	No	Course context (e.g., "course_60366")
`recipient_ids`	Yes	List of Canvas user IDs
`attachment_ids`	No	Optional attachment IDs
`course_identifier`	Yes	Course code or Canvas ID
`confirmation_token`	No	Token from the preview call (multi-recipient only)
`group_conversation`	No	Create group conversation (required for custom subjects)

Output Schema

TableJSON Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

Changed24 schema fields changedv1.8.0Aug 10, 2026
- addedInput schema / additionalProperties
```
Added value: +false
```
- addedInput schema / properties / attachment_ids / description
```
Added value: +"Optional attachment IDs"
```
- removedInput schema / properties / attachment_ids / title
```
Removed value: -"Attachment Ids"
```
- addedInput schema / properties / body / description
```
Added value: +"Message content"
```
- removedInput schema / properties / body / title
```
Removed value: -"Body"
```
- addedInput schema / properties / bulk_message / description
```
Added value: +"Send individual messages with same subject to each recipient"
```
- removedInput schema / properties / bulk_message / title
```
Removed value: -"Bulk Message"
```
- addedInput schema / properties / confirmation_token
```
Added value: +{
+  "anyOf": [
+    {
+      "type": "string"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "description": "Token from the preview call (multi-recipient only)"
+}
```
- addedInput schema / properties / context_code / description
```
Added value: +"Course context (e.g., \"course_60366\")"
```
- removedInput schema / properties / context_code / title
```
Removed value: -"Context Code"
```
- addedInput schema / properties / course_identifier / description
```
Added value: +"Course code or Canvas ID"
```
- removedInput schema / properties / course_identifier / title
```
Removed value: -"Course Identifier"
```
- addedInput schema / properties / force_new / description
```
Added value: +"Force new conversation even if one exists"
```
- removedInput schema / properties / force_new / title
```
Removed value: -"Force New"
```
- addedInput schema / properties / group_conversation / description
```
Added value: +"Create group conversation (required for custom subjects)"
```
- removedInput schema / properties / group_conversation / title
```
Removed value: -"Group Conversation"
```
- addedInput schema / properties / mode / description
```
Added value: +"\"sync\" or \"async\" (use async for >100 recipients)"
```
- removedInput schema / properties / mode / title
```
Removed value: -"Mode"
```
- addedInput schema / properties / recipient_ids / description
```
Added value: +"List of Canvas user IDs"
```
- removedInput schema / properties / recipient_ids / title
```
Removed value: -"Recipient Ids"
```
- addedInput schema / properties / subject / description
```
Added value: +"Message subject (max 255 chars)"
```
- removedInput schema / properties / subject / title
```
Removed value: -"Subject"
```
- removedInput schema / title
```
Removed value: -"send_conversationArguments"
```
- removedOutput schema / title
```
Removed value: -"send_conversationDictOutput"
```
Changed1 schema field changedv1.0.0Jan 3, 2026
- addedInput schema / title
```
Added value: +"send_conversationArguments"
```
First observedSep 27, 2025

TDQS

A4.6/5.0

Behavior5/5

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

Beyond the annotations (idempotentHint=false, destructiveHint=false), the description discloses the token lifecycle: it expires, is single-use, and becomes void if any argument changes. It also explains that a preview must be shown to the educator, adding significant context about expected behavior.

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?

The description is compact and front-loaded: the first sentence states the core purpose, and the two-step flow is explained in a structured, readable block. There are no unnecessary sentences or redundancy.

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 of 11 parameters and a multi-step flow, the description covers the most critical behavioral nuance (the preview/confirm mechanism). An output schema exists, so not describing return values is acceptable. It could mention permission prerequisites, but the description is largely complete.

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 input schema already describes all 11 parameters (100% coverage). The description adds key semantics for confirmation_token—it is required for the second step of a multi-recipient send and all other arguments must be identical to the preview. This extra context goes beyond the schema, but not all parameters are addressed.

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 opens with a clear verb+resource: 'Send messages to students via Canvas conversations.' It clearly states what the tool does and is specific enough to distinguish from siblings like list_conversations or send_bulk_messages_from_list by identifying the conversation channel.

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 explicitly explains the single-recipient vs. multi-recipient workflows, including the two-step preview-confirmation process. However, it does not mention alternative tools (e.g., send_bulk_messages_from_list) or when NOT to use this tool, which prevents a score of 5.

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

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