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 value by disclosing the return content ('event descriptions, years, and details'), which goes beyond the annotations and gives the agent a clearer picture of the tool's output behavior.

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 two short sentences, front-loaded with the core action and then detailing parameters and returns. Every word earns its place with no redundancy or 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 simple two-parameter tool with a well-defined input schema and an output schema present, the description provides enough context: what it does, what parameters are needed, and what it returns. It does not mention potential limitations (e.g., pagination, date range boundaries), but given the tool's simplicity and annotation coverage, this is not a significant gap.

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 already provides 100% coverage with descriptions for both 'month' and 'day', including their ranges. The description's mention of 'month (1-12) and day (1-31)' largely repeats the schema, adding no new semantic depth, 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 clearly states a specific verb ('Search') and resource ('historical events') with a date qualifier, making the tool's purpose unambiguous. It does not explicitly differentiate from sibling tools like get_births or get_deaths, but the term 'historical events' implies a broader scope, earning a 4 rather than a 5.

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 implies when to use the tool: for searching historical events on a specific date, with required month and day parameters. However, it provides no explicit guidance on when not to use it or how it relates to alternative sibling tools such as get_births or get_deaths, so the context is clear but exclusions/alternatives are missing.

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