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

Annotations already cover the safety profile (readOnly, not open-world). The description adds real scope disclosure beyond that: 'every meeting in our data (all competitions, no friendlies)' and 'history_from: our data starts there, so say since that date' — a data-coverage limitation an agent would otherwise not know.

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?

Purpose is front-loaded, but the rest is a dense run-on cramming sports list, output fields, perspective rules, sentence languages, and history_from into one block. Because there is no output schema the content is needed, yet the packing hurts scannability.

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 no output schema, the description carries the return-format burden and does so thoroughly (records, goals, biggest wins, recent meetings, generated sentences). The trailing 'Facts only. Insights feature.' is cryptic and never explained, a minor 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% so the baseline is 3, but the description goes further: it defines the perspective semantics ('won, drawn and lost from team_a's side; home_team_* fields = team_a'), which meaningfully disambiguates team_a vs team_b beyond the schema's terse 'team code'/'the other team's id'.

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?

Names the specific operation (head-to-head between two teams) and enumerates the exact return content: wins/draws/losses from team_a's side, goals, biggest wins, last 5 meetings. It also carves out tennis explicitly via get_player, so an agent can distinguish this from sibling lookups like get_match or get_team without opening a 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?

The tennis carve-out ('Tennis: get_player with vs') gives one explicit alternative route, and 'soccer by default' plus the sport list tells the agent which inputs are valid. It lacks a general when-to-use statement, but the head-to-head framing plus the tennis redirect is clear context.

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