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

Annotations already cover read-only, idempotent, and non-destructive behavior. The description adds valuable behavioral context beyond those flags: it characterizes the search as 'typeahead' and clarifies that the output is a slug suitable for other tools. It does not disclose result limits or response format, but with annotations present, this is acceptable.

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?

Two compact sentences: the first defines scope and behavior, the second states the intended use. No filler, and the action is front-loaded, making it easy for an agent to parse quickly.

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 one-parameter read-only search tool, the description covers the essential invocation context: what is searched, typeahead behavior, and the purpose of the output. It omits response structure details, but that is a minor gap given the simple input and strong annotations.

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 schema only describes q as a string with minLength 2. The description enriches this by explaining that q is the name a user typed and that the tool converts it to a slug, adding meaning that the schema alone does not convey.

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 (search) across two resources (fighters and events) and emphasizes 'in one call', which distinguishes it from narrower sibling tools like search_fighters. The scope and action are immediately clear.

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 second sentence gives explicit usage context: use it when a user has typed a name and you need a slug for other tools. However, it does not name alternatives or state when not to use it, so it lacks the explicit exclusion/alternative guidance needed for a 5.

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