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

Annotations already signal read-only, and the description adds an operational cost ('Costs 5 credits') that an agent needs before calling. No mention of row limits or response behavior, but with readOnlyHint true and an output schema present the bar is lower.

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 core purpose and scopes, with the cost detail at the end. No filler.

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 output schema, readOnly annotation, and high schema coverage, the description supplies the selection-relevant mode context and cost. It could be more explicit about required parameter combinations since all six params are optional, but it is adequate for a query tool of this complexity.

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 has 100% coverage, so baseline is 3. The description adds mode-level semantics by mapping 'one game, one player (PFR id), or a team's season' to the available lookup styles, which is useful beyond terse property descriptions. It stops short of stating which parameter combinations are required.

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?

Description names the resource (snaps and snap shares by offensive/defensive/special-teams) and the supported scopes (game, player, team season), making the tool's role clear. It does not explicitly distinguish it from sibling stats tools such as get_player_stats or get_team_stats, so it lacks the differentiator needed for a 5.

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?

Begins with 'Use for playing time', giving a direct usage context, and spells out the three query modes. It does not mention alternatives or exclusions, so it falls short of a 5.

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