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

Annotations already establish that this is a read-only, open-world operation. The description adds useful behavioral context by naming the returned data and explicitly excluding pools, payouts, bet IDs, and participant personal names, though it does not discuss rate limits or access requirements.

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 compact sentences front-load the core action and prerequisite, then list returned and excluded data. Every clause contributes useful selection or scoping 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?

For a one-parameter read-only tool with annotations and an output schema, the description is largely complete: it identifies the source of race_id and the contents of the race card. The only minor gap is that it does not detail authentication, pagination, or rate-limit behavior.

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 already documents race_id as coming from the public Racing schedule. The description reinforces the source but adds no syntax, format, or validation detail beyond the structured field definition.

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: fetch one DraftKings Racing race card by race_id. It also distinguishes the tool from the schedule sibling by clarifying that this returns a single race card with horse-level details.

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 clearly indicates the required race_id comes from draftkings_racing_schedule, giving an actionable prerequisite. It does not explicitly compare against other sibling tools or state when not to use this tool, but the usage context is clear.

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