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

With no annotations, the description carries the burden and does disclose the key destructive behavior: mail stops immediately and existing messages become unreadable. It does not explicitly say whether deletion is permanent/irreversible or describe permission/error behavior, so it is strong but not fully comprehensive.

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 short, front-loaded with the consequence of deletion, and each sentence adds useful information: effect, usage condition, and next step. There is no wasted text.

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 one-parameter destructive tool with no output schema, the description covers the main behavioral consequence and the follow-up action. It could be more complete by explicitly stating irreversibility or any auth/permission caveats, though the read_token schema already covers authentication mechanics.

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 100%, and the single read_token parameter is already documented in the schema as coming from create_inbox or Authorization: Bearer. The description adds no parameter-level detail beyond the schema, which is appropriate for high coverage.

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 gives a specific verb and resource ('Delete an inbox') and immediately states the effect: it stops accepting mail and messages become unreadable. It also distinguishes this from the sibling create_inbox by naming the create path as the next step.

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 clearly says when to use it ('when you are done with a signup') and points to create_inbox as the alternative for getting a new address. It does not explicitly state when not to use it, but the immediate mail-stopping behavior makes that implication clear.

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