mailbox_receive

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

Annotations declare readOnlyHint=true and destructiveHint=false, but the schema contains a 'remove' boolean defaulting to true, suggesting the tool may consume or delete the message. The description does not disclose this side effect or explain waiting/blocking behavior for an empty mailbox. The safety annotations provide some context, but the most important behavioral nuance is hidden.

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 a single, front-loaded sentence with no filler. It is concise, though somewhat under-sized given the behavioral details that need to be covered; it earns points for efficiency but not for completeness.

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?

There is no output schema and the description does not explain return values, empty-mailbox behavior, blocking semantics, or the default removal side effect. For a tool with one required parameter and a behavioral switch, this leaves too much for the agent to guess.

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%, and the description does not explain either parameter. An agent can infer that 'inbox' identifies the mailbox, but the meaning of 'remove' — whether the message is deleted after retrieval and that it defaults to true — is entirely undocumented. The description does not compensate for the schema gap.

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 states a specific verb and resource: 'Receive one NXT mailbox message.' This clearly identifies the operation and is distinguishable from the sibling mailbox_send. It could be stronger by explicitly naming the inbox/source, but the core purpose is unambiguous.

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 intended use is implied by the verb 'receive': an agent would use this when it needs to retrieve a mailbox message. However, the description gives no explicit guidance about when not to use it, does not reference mailbox_send as the alternative, and does not mention conditions such as handling an empty mailbox.

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