sms_rental_messages

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

With no annotations, the description carries the full behavioral burden and does supply one genuinely useful fact: orderId doubles as the authentication secret, and the call is free. It stops short of stating return format, behavior when no SMS has arrived, or rate limits.

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?

Very short and front-loaded, which is good, but '(free)' appears twice in parentheses — a duplicated parenthetical that wastes space in an already minimal description.

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 no-annotation, no-output-schema tool this is thin. Nothing explains the response shape, whether messages accumulate, or what an empty result means — all of which an agent needs to use a polling endpoint 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 coverage is 0% — the single orderId parameter is typed string with no explanation. The description partially compensates by explaining orderId's role as the secret/auth token, which is meaningful beyond the schema, but it does not say where that ID comes from.

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?

States a specific verb+resource: read SMS received on a rented number. The 'rented number' qualifier distinguishes it from the broader sms_* and mail_* siblings, though it never names sms_rental_order (which provisions the number) as the counterpart.

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?

Usage is only implied — the agent must infer that this is polled after sms_rental_order to retrieve verification codes. No explicit when-to-use, when-not, or alternative tools are named, and no guidance on polling cadence.

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