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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description usefully scopes the data to "current public" cards and rules out wagering/favorite-track content, but says nothing about refresh cadence, time zone of post times, or pagination behavior.

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 sentences, both earning their place: the first defines scope and fields, the second gives the usage cue and exclusions. No redundancy and the core purpose is front-loaded.

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 zero-parameter, read-only listing with an output schema already covering return structure, the description is close to complete. The one meaningful omission for a schedule tool is any note on time zone or how current the "current" cards are.

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 tool takes zero parameters, which is the baseline-4 case; the schema has nothing for the description to clarify. The description instead documents the shape of the result set (track, race number, post time, status), which is helpful but belongs to the output side.

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 (List) and resource (current public race cards on DraftKings Racing) and enumerates the returned fields (track, race number, post time, status). It implicitly separates itself from the betting-oriented siblings by noting it excludes wagering data, though it never names draftkings_racing_tracks or draftkings_odds directly.

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?

"Use it to browse today's schedule" gives a clear use context, and the exclusion clause tells the agent what not to expect from it (favorite-track and wagering data). It stops short of naming the alternative tool an agent should call for odds or betting lines.

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