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

Annotations already declare readOnlyHint, idempotentHint, and closed-world, so safety is covered. The description adds genuinely new behavior: an empty result set with a note when no draws occurred, and the restriction to official results only — useful operational context beyond the 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?

Three short sentences with zero padding. The core scope is front-loaded, followed by the empty-result edge case and the official-only boundary; every sentence earns its place.

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 simple one-parameter read tool with full annotation coverage, the description covers scope, edge-case return behavior, and content boundaries. No output schema exists, but the description adequately characterizes what comes back, so nothing critical is missing.

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 the YYYY-MM-DD / MYT format. The description only refers to 'a given calendar date' and adds no format, timezone, or boundary semantics beyond what the schema provides; baseline 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?

States a specific verb and resource ('Returns every operator's official 4D draw result') plus the scoping key ('for a given calendar date'), so an agent can distinguish it from get_latest_results and get_operator_results without opening a schema.

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?

Usage is implied by the date-scoped framing and the exclusion of 'number recommendations or forecasts', but the description never explicitly says when to prefer this over the sibling get_operator_results or get_latest_results. No when-not guidance beyond the exclusions.

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