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

Annotations already declare readOnlyHint=false, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds real context beyond that: it is free with a quota of 30 turns/day in trial and 300 after, it works pre-verification, and it exercises only the brain and personality rather than face or voice.

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?

It is front-loaded with the action and return value, then layers in the timing window, history format, quota and scope limitation. Every sentence carries information, though the history parenthetical is dense and slightly interrupts the flow.

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?

With an output schema present, return values need no explanation, and the description covers timing, cost/quota, history shape and scope limits. The only notable omission is that the id parameter is never explicitly identified as the Nod's id, and history is not tied to the schema's 24-item cap.

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%, so the description must carry parameter meaning, and it does for the hardest one: history is explained as earlier turns, oldest first, each with role user or assistant and a field named text, not content. The id and text parameters are left to obvious inference, which is a minor 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 concrete verb and resource: it sends one message to a Nod and returns its answer, using that Nod's name, personality and brain. The final sentence separates this from the room-based face and voice path, which helps distinguish it from send_nod, though it never names that sibling outright.

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 gives a clear usage window: works right after create_nod, before the owner verifies, and is meant for testing a short conversation via the history array. It lacks an explicit 'use send_nod instead when...' routing statement, so the alternative is only implied by the face/voice contrast.

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