Update the content of a previously sent direct message to a Discord user using their user ID, the message ID, and the new text.
Edit a previously sent direct message to a user
| Name | Required | Description | Default |
|---|---|---|---|
| userId | Yes | Discord User ID | |
| messageId | Yes | Message ID to edit | |
| newMessage | Yes | New content for the direct message |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It states the operation is an edit (a mutation) but doesn't disclose permissions required, whether edits are allowed on others' messages, if history is tracked, or what happens on failure. Significant behavioral gaps for a mutation tool.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single, clear sentence with no wasted words. It is appropriately sized for the tool's simplicity and front-loads the action.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given it's a mutation tool with no annotations and no output schema, the description is too sparse. It should explain permissions, return behavior, or error conditions to be truly complete for an agent.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100%, so all three parameters (userId, messageId, newMessage) are already documented in the schema. The description adds no additional meaning beyond what the schema provides. Baseline 3 is appropriate when schema does the heavy lifting.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
Clear verb 'Edit' and resource 'direct message' with a specific scope ('previously sent'). However, it does not distinguish from siblings like edit_message (likely for channel messages) or other DM tools like send_direct_message and delete_direct_message.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No explicit when-to-use or when-not-to-use guidance. The phrase 'previously sent' implies the message must already exist, but there's no mention of alternatives like edit_message for server messages or restrictions on which messages can be edited.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.