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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds real value beyond that by disclosing what is returned (numbers, bonus numbers, jackpot amounts) and constraining the tool to official results with no forecasts, though it says nothing about data freshness or draw coverage.

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, front-loaded with the verb and scope, with the long game enumeration and the official-results caveat both earning their place. No filler or restatement of the tool name.

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?

There is no output schema, so the description correctly carries the return-value burden by naming numbers, bonus numbers and jackpot amounts. The limit parameter is left entirely to the schema, and freshness/latency of results is unaddressed, which is a minor gap for a results-lookup tool.

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 100%, so the baseline is 3, but the description goes further by mapping enum slugs to real-world game names (Toto 5D/6D/Star/Power/Supreme, Magnum Life/Jackpot/Gold, Da Ma Cai 3+3D/Jackpot, Singapore Toto). That mapping helps the agent pick the right slug.

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 official results) and scopes it precisely to 4D-family games other than the main draw, enumerating the supported games. An agent can distinguish it from get_latest_results or get_operator_results without opening any 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?

The scope clause ('games other than the main draw') gives clear context for when this tool applies, and 'Official results only; no number recommendations or forecasts' rules out a misuse class. However, no sibling tool is named as the alternative for main-draw results, so the routing is implied rather than explicit.

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