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

Adds real context beyond the readOnly/openWorld/idempotent annotations: results are capped and the trailer reports how many were hidden, and each call costs one live API request against the plan with an instruction to reuse ids. That cost and truncation disclosure is exactly the kind of behavior an agent cannot infer from the schema or annotations.

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?

Front-loads what the tool returns, then the routing instruction, then filtering syntax, then cost/pagination caveats. Five dense sentences with no filler; each one carries distinct information.

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 still characterizes the return (compact rows, moneyline, response_format effect) and the truncation trailer, and warns about per-call cost. For a 5-param, read-only search tool an agent has everything needed to call it correctly.

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 description coverage is already 80%, so the baseline is 3. The description goes further on the highest-value parameter by explaining query semantics (space-separated, all words must match league/home/away, case-insensitive) with a concrete example, though limit's cap is only referenced indirectly as 'capped'.

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 (list events) with scope qualifiers (live or upcoming/prematch, one sport) and output shape (compact rows with full-match moneyline). It is clearly distinguishable from get_event_odds (odds detail) and get_prematch_lines.

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?

Explicitly routes the agent: 'Use it to find event ids before calling get_event_odds' gives a concrete when-to-use and names the follow-on tool. It does not, however, address when to prefer it over the overlapping get_prematch_lines for upcoming fixtures, so the guidance is clear but not exhaustive.

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