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

Annotations already declare readOnlyHint=true, openWorldHint=false and destructiveHint=false, so safety is covered. The description adds genuinely new behavior: a hard cap of five results and accent/case-insensitive matching, which affects how an agent should phrase retries. It stops short of saying what happens on zero matches, so not a 5.

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?

Three short sentences, each doing distinct work: purpose, workflow routing, input rules. The most important information (what it returns and that it should be called first) is front-loaded with zero 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?

Single-parameter tool with no output schema, and the description still discloses the result cardinality and per-result fields, plus matching behavior. There is nothing an agent needs in order to call this correctly that is missing.

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 0% — the schema only carries minLength/maxLength with no descriptions — so the description must compensate, and it does: '2 to 60 characters' restates the bounds usefully and 'accents and case are ignored' adds matching semantics found nowhere in the schema. It does not clarify whether multi-word or partial names are matched, keeping it below 5.

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?

States a specific verb and resource ('Finds clubs and leagues by name') plus the result shape ('up to five, each with its 442ball slug and page URL'). That return contract makes it clearly distinguishable from every sibling (club_rating, league_index, rankings), all of which consume the slug this tool produces.

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?

'Use it first when you have a name, then pass the slug to the other tools' gives an explicit ordering rule and names the downstream consumer, which is the whole sibling set. An agent knows both when to call this and what to do with the result.

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