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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety toward this tool is established. The description adds the 1-50 character bound, the 'public suggestions' nature, and the note that the response preserves upstream JSON, but says nothing about rate limits, result caps, or auth. Some added value above annotations, 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?

Two tight clauses with zero filler; the core purpose is front-loaded and the sibling routing is appended after it, so an agent reads the essential fact first.

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 need not explain return values, and annotations cover the safety profile. It is nearly complete, though it does not mention any result count or pagination behavior for a search endpoint, leaving a small 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?

Schema coverage is 100%, and the schema's own description already states 'Required search phrase, 1 to 50 characters. Returns matching leagues, teams, players, and matches.' The description only restates the term length, adding no syntax or format detail beyond the schema, so baseline 3 applies.

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 ('Search') and resource ('FotMob public suggestions for leagues, teams, players, and matches'), and explicitly delimits scope as suggestion-style lookup rather than detail retrieval. An agent can distinguish it from sibling detail tools without opening any schema.

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?

Names concrete alternatives and the condition that selects them: 'Use fotmob_leagues, fotmob_team, or fotmob_matches to retrieve details, or fotmob_trending_searches for popular queries.' This gives clear when-to-use-else routing that no sibling search tool provides.

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