Delete Message

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

While annotations already indicate destructiveHint: true, the description adds the crucial behavioral detail that 'confirm=True' is required for the deletion to proceed. This is not evident from the schema alone and helps the agent understand the safety gate. No contradiction with annotations.

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?

The description is extremely concise with two sentences, no extraneous information. It front-loads the purpose and immediately follows with the critical usage requirement. Every word earns its place.

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 the tool's simplicity (2 params, no nested objects) and the presence of an output schema, the description covers the key behavioral nuance (confirm required). However, it does not address what happens if confirm is false or potential error states, leaving minor gaps for edge cases.

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 0%, so description must compensate. It adds meaning by specifying that message_id is a 'canonical id' and that confirm must be set to true for the action to occur. This provides essential context beyond the schema's boolean default, though it does not detail the format of message_id.

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 clearly states 'Delete a Mail message by canonical id.' It uses a specific verb (Delete) and resource (Mail message), and distinguishes this tool from siblings like mail_move_message or mail_flag_message by focusing on deletion. The mention of 'canonical id' adds specificity.

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?

The description says 'Requires confirm=True,' which gives a usage condition but does not explicitly state when to use this tool versus alternatives (e.g., mail_move_message for trashing). There is no guidance on when not to use it or mention of alternatives, leaving the agent to infer context from sibling names.

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