Rate a message you received

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

With no annotations, the description carries the full burden and does substantial work: it discloses that ratings stay local to the machine, that they change how the sender's messages are routed (pausing ordinary messages from noisy senders), and that they score the router. It omits any mention of what the call returns or whether ratings can be changed/undone, which is a gap for a mutation-style tool.

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?

One long but well-ordered passage: purpose first, then rating semantics, then side effects, then the default fallback. The clause about scoring the router is mildly tangential but earns its place by explaining why ratings matter. No redundant filler.

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 3-parameter tool with no annotations and no output schema, the description covers purpose, semantics of each enum value, privacy, and side effects. The main omission is return-value behavior, which the absence of an output schema pushes back onto the description.

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 100%, so the baseline is 3, but the description adds meaning the schema does not: it states that omitting both message_id and from rates the latest message received, which is the default-resolution behavior an agent needs to know. The three enum values are also restated with their interpretation.

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?

Names a specific verb (rate) and resource (a message another session sent you), then defines all three rating values inline so the agent knows exactly what each option means. It is clearly distinguishable from siblings like message_status (inspect) and send_message (produce).

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 clearly frames the context of use — judging a message you already received — and explains the downstream purpose of rating (tuning routing and scoring the router). It does not explicitly contrast with siblings such as message_status, but the usage condition is unambiguous.

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