read_messages

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

No annotations are provided, so the description carries the burden. It discloses useful behavioral details: messages are returned newest-first and the default direction is 'in' for a specific reason. However, it does not clarify whether reading affects read state, what the response shape is, or whether there are any limits or pagination.

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?

Every sentence earns its place: a short action-oriented first sentence, a parameter definition, and a rationale for the default. There is no redundant content or padding.

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 low-complexity read tool with only two parameters, the description has all the essential calling information: what to read, which inbox, ordering, and direction semantics. The main omission is what exactly is returned and whether there are any limits, but these were not be blocking for a basic read operation.

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 only 0%, but the description compensates well. It fully explains the direction parameter with all three values ('in', 'out', 'all'), states the default, and explains the reasoning behind the default. The address parameter is also clear from the phrase 'given inbox address'.

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 ('Read messages') and a specific resource ('the given inbox address'), plus the ordering ('newest first'). This is enough to distinguish read_messages from siblings like send_email, delete_message, or mark_read.

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 explains the direction parameter and why the default is 'in' so that a sent message is not confused with an awaited reply. However, it does not explicitly say when to choose this tool over alternatives such as wait_for_message or list_inboxes; the guidance is implied rather than stated.

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