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

Annotations already declare read-only/idempotent/non-destructive, so the safety burden is covered. The description adds useful behavioral context: updated twice a week, scope limited to WR/TE/RB, and it is a ranking rather than a weekly projection.

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?

Despite its length, the description is front-loaded with the core purpose and metric definitions, then covers views and caveats. Every clause carries information, though a bulleted structure would improve readability.

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?

With no output schema and 14 parameters, the description enumerates the returned fields (player_value, system_lift, etc.) and view modes, so an agent knows what to expect. It omits pagination details and auth needs, but annotations and schema descriptions cover those.

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 64%, and the description adds meaning beyond the schema for several parameters: it explains the three view modes, what 'player' does, and the concepts behind role/route_profile/archetype filters. It does not clarify limit/offset, sort_dir, position, or block beyond what the schema already provides.

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 (NFL Player Index for WR, TE, RB) and decomposes its output into named metrics. It explicitly contrasts itself with a sibling category ('not a weekly projection'), so an agent can distinguish it from projection tools.

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?

Gives explicit guidance for the view parameter (players default, give player for single-player history; systems for coach/QB lift; coach_roles for coach averages) and a when-not ('not a weekly projection'). However, it does not name alternative tools or say when to choose this over invoke_nfl_player_pool.

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