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

Annotations declare destructiveHint=true and readOnlyHint=false, but the description presents a harmless retrieval operation. It omits deletion side effects, irreversibility, required permissions, and any warning that the message may be removed.

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 main sentence is concise and front-loaded with the resource and returned fields. The embedded pricing boilerplate is irrelevant to invocation, but the description remains structurally efficient overall.

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 destructive operation with no output schema and annotations indicating deletion, the description should carry critical context such as deletion warnings, irreversibility, and permissions. Instead it describes retrieval, leaving the agent without the information needed to call the tool safely or correctly.

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%, so inbox_id and message_id are fully documented in the input schema. The description adds return-content context but no additional parameter syntax or semantics beyond what the schema already provides.

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 says to retrieve message details, but the tool name is delete_agentmail_inbox_message and a sibling get_agentmail_inbox_message exists. This gives an agent the wrong operation verb, making the purpose misleading despite mentioning sender, recipients, content, labels, attachments, and timestamps.

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 when-to-use guidance, prerequisites, or alternatives are provided. It does not distinguish this tool from get_agentmail_inbox_message or explain when a message should be deleted versus retrieved.

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