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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds that the call is paid (US$0.02) and that the snapshot is 'compact derived', offering some insight into processing. However, it does not disclose error behavior, latency, or what happens if the horse identifier is invalid. Given the annotations, this is adequate but not rich.

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 concise: two short sentences with no fluff. The pricing information is deliberately front-loaded, which is important for autonomous calls. The structure is clean and scannable.

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?

The tool lacks an output schema and provides no description of the snapshot's contents, format, or how to handle the horse identifier. Given the number of sibling tools (horse_changes, horse_compare, etc.), the description does not provide enough context to help an agent choose correctly or know what to expect.

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?

The description makes no mention of the 'horse' parameter, its expected format, or how it should be supplied. With 0% schema coverage and only a string type in the schema, the agent is left with no additional meaning. This is a critical gap for a tool with a required parameter.

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 clear action: 'Return a compact derived operating snapshot for one horse.' It specifies the resource (horse) and the type of output (snapshot). It does not explicitly distinguish from siblings like horse_explanation or horse_signal, but the term 'snapshot' implies a concise operational view, which is reasonably distinct.

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 provides pricing details but no guidance on when to use this tool versus alternatives. There is no mention of scenarios where this tool is preferred over horse_intelligence, horse_signal, or horse_rankings. An agent is left to infer usage from the name and description alone.

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