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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds one useful behavioral pointer – that accepted filter values come from mlb_discovery – but says nothing about pagination limits, row defaults, or return shape beyond what the output schema carries, so it earns only partial credit over the annotations.

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 tight sentences, scope and routing front-loaded, zero filler. Every clause earns its place by either describing the resource or dispatching to a sibling tool.

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 17-parameter query tool with no required params, a full output schema, and annotations covering safety, the description supplies the essential routing and filter-source context. It omits only minor operational detail (e.g., that with_team_only needs a single team id), which the schema already states.

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 every parameter already documents its meaning and default. The description's enumeration of filter categories (season, outcome, base, team, sort, page) adds little beyond the schema; it neither introduces syntax nor clarifies the with_team_only/team coupling, so baseline 3 is appropriate.

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 ('Fetch') plus resource ('Baseball Savant Running Game rows') and the actor scope (pitchers, teams, or league), which precisely identifies the table. It further names the two sibling tools it must be distinguished from, so an agent can separate it from mlb_statcast_running_game_details and mlb_statcast_baserunning without opening schemas.

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?

Explicitly routes: use mlb_statcast_running_game_details for a play, mlb_statcast_baserunning for runner metrics, and mlb_discovery for accepted filters. It names alternatives with the condition that selects each, leaving nothing to inference.

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