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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and open-world behavior are covered. The description adds genuine scope context (only primary markets — moneyline/spread/total — not all markets, and all upcoming events in the league), but says nothing about freshness/live pricing, rate limits, or whether upcoming excludes live events (draftkings_live exists as a sibling).

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?

One tightly written sentence with the resource, the market types, and the scope all front-loaded; there is no filler to remove.

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?

An output schema exists, so return values need not be explained. However, for a tool whose only input is an opaque league_id, the description leaves the agent without the identifier format or a pointer to the league-listing siblings, which is the main practical 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 description coverage is 0% and the single required parameter league_id carries no description or enum. The description mentions 'in a league' but never explains the expected league_id format (slug vs. numeric id) or how to obtain a valid value, so it fails to compensate for the schema gap.

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 resource (DraftKings Sportsbook primary betting markets) with concrete scope (moneyline, spread, total) and coverage (every upcoming event in a league). Clear on its own, but it never distinguishes itself from the close sibling draftkings_event_markets, which by name appears to serve a similar market-data purpose at event granularity.

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?

There is no when-to-use guidance: no statement that a league_id from draftkings_leagues/draftkings_featured_leagues is required, no exclusion for single-event lookups, and no mention of draftkings_event_markets or draftkings_futures as the alternatives for those cases. The agent must guess the routing.

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