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

With no annotations, the description carries the full burden. It discloses that the tool is free, requires no auth/payment, and returns a sample of one matchup. However, it does not explain what 'full-depth sample' includes, output format, or any limitations beyond the single matchup.

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?

The description is a single, tightly-worded sentence that front-loads the 'FREE' hook and quickly conveys the purpose and access requirements. Every word contributes value with no redundancy.

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?

Given the tool's extreme simplicity (0 params, no annotations, no output schema), the description is somewhat adequate but leaves ambiguity about what 'full-depth sample' contains and what sports are featured. It could clarify the nature of the data returned.

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 has zero parameters, so the description need not add parameter details. Baseline for 0 params is 4, and the description correctly implies no input is needed ('pick-of-the-day').

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?

The description clearly states that this tool provides a free sample of the sports engine on one featured matchup. It uses a specific verb ('scan' implied by the name, and 'sample') and distinguishes itself from sibling scan_* tools by being a free 'pick-of-the-day' preview.

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?

It implies usage for a free trial or demo by emphasizing 'FREE' and 'No auth, no payment', but does not explicitly contrast with alternatives like scan_compare or signal_sports. It gives context (sports engine, one matchup) but lacks clear when-not-to-use guidance.

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