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

Annotations already declare destructiveHint=true and readOnlyHint=false. The description adds critical behavioral details: cascading deletion of replies and irreversibility. It also specifies 'your own' as a permission constraint. This goes beyond the annotations without contradicting them.

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?

Two sentences with zero waste. The primary action is front-loaded, followed by the critical cascade and irreversibility warnings. Every word contributes to the meaning.

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?

For a simple single-parameter destructive tool with annotations covering safety and an output schema present, the description covers the essential behavior: scope, cascade, and irreversibility. It does not mention error conditions (e.g., non-existent message, permission denied), but these are not critical for invocation.

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 description coverage is 0%, meaning the description does not explicitly document the message_id parameter. However, the single parameter is self-evident from the tool name and schema title ('Message Id'). The description does not add format or constraints, but the simplicity of the parameter and the tool's clear purpose justify a baseline score of 3.

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?

The description explicitly states the verb 'delete', the resource ('your own message'), and the cascading behavior for root messages. This clearly distinguishes it from sibling tools like board_edit (modify), board_hide (conceal), and board_lock (restrict) without ambiguity.

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?

It states 'your own message', implying a restriction to own messages only, and warns that deletion is irreversible. This provides clear usage context, though it does not explicitly name alternative tools or contrast scenarios (e.g., when to use board_hide instead). The guidance is sufficient for an agent to decide when to invoke it.

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