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

With no annotations provided, the description carries the full behavioral disclosure burden and discloses genuinely useful traits: lookback defaults and maximums, sorting behavior by absolute movement, and tier gating (Free locked, Starter gets a limited board, Pro gets the full board). It does not cover what happens when stat/sport/limit are omitted, but the disclosed behaviors substantially exceed what the schema alone conveys.

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 dense sentences with the core function, window behavior, and sort order front-loaded, followed by access-tier context. Every sentence earns its place and there is no filler or repetition of schema content.

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 scan tool with four optional parameters and no required ones, the description explains the core behavior and tiering but does not state what a no-parameter call returns or what the response looks like. With no output schema and no annotations, these gaps leave an agent to guess about default boards and return format.

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 75%, so the schema already documents stat, since, and sport; the description reinforces the since parameter's default and maximum, which overlaps rather than adds. It contributes nothing for limit, the one parameter lacking a schema description, and does not explain how omitting stat or sport affects the returned board.

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 first sentence states a specific function: returning props whose line moved most within a lookback window, with explicit sort order (absolute movement), a default window (24h), and a max (7d). This is clear and concrete, though it does not explicitly differentiate itself from the similarly named sibling scan_props.

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 guidance on when to select this tool over alternatives. With 11 siblings including the closely named scan_props, the description never steers the agent between 'props that moved the most' and a general prop scan or prop history lookup. The tier-gating sentence is about access levels, not usage selection.

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