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

Annotations already declare readOnlyHint and idempotentHint, so the description adds value by disclosing behavior like daily snapshots and deduplication per calendar day, and the trend summary format. This goes beyond what annotations provide and does not contradict them.

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 four concise sentences, each adding distinct value: purpose, data structure, output summary, and a use case. It is front-loaded with the main purpose and contains no redundant or vague language.

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, the description sufficiently covers what the tool does and returns (daily snapshots, trend summary) and the intended use case. It could mention edge cases or ordering, but the combination of schema, annotations, and description is largely complete for selecting this tool.

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 input schema provides 100% coverage with descriptions for both 'days' and 'handle'. The description only reiterates the time range from the schema (1–90 days) and adds no new parameter semantics, so the baseline of 3 is appropriate.

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 ('Get') and resource ('rank and score history') with a clear time scope ('past 1–90 days'), distinguishing it from siblings like get_agent_details or get_agent_changes. It also specifies the output includes daily snapshots and a trend summary, which is unique to this tool.

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 a clear use case ('Useful for showing how an agent's standing has evolved'), giving context for when to use the tool. However, it does not explicitly name alternatives or state exclusions, so it falls short of the highest level.

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