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

With no annotations provided, the description carries the full transparency burden. It discloses the aggregation period (3 years), scope (GB & IRE flat courses), metrics, and grouping by stall third, course, surface, and distance band. It does not, however, describe the output format or default behavior when no course parameter is supplied, which is covered only in the schema.

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?

The description is a single, information-dense sentence that front-loads the tool's purpose and immediately lists the metrics and grouping dimensions. No wasted words; every element adds value.

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 tool with one optional parameter, no annotations, and no output schema, the description provides substantial context: time range, geography, race type, and metrics. It lacks explicit return-structure details, but given the simplicity of a single-parameter query, the description is almost complete. Would be a 5 with clarity on what is returned when the course filter is omitted.

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 fully covers the single optional 'course' parameter with an example ('lingfield'), giving 100% schema coverage. The description does not add information about parameters beyond what the schema already provides, so a baseline of 3 is appropriate.

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 clearly states it provides 3-year draw-bias aggregates for GB & IRE flat courses, listing the specific metrics (IV, A-E, PRB) and grouping dimensions. This distinguishes it from sibling tools like get_today_races and get_race_signals, which focus on different data.

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 description implies usage for accessing historical draw-bias statistics on flat courses, but offers no explicit guidance on when to use this tool versus alternatives like get_combo_stats or get_race_signals. No 'when to use' or 'when not to use' is stated.

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