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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and external-data scope are covered. The description adds the filtering/pagination surface, but does not disclose row counts, ordering defaults, or whether results are cached/live beyond what the schema already says.

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 front-loaded sentences with no filler; the purpose leads and the filter/routing detail follows. Dense but clean, with only mild enumeration padding.

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?

An output schema exists and the full parameter set is documented, so return values need not be explained. Combined with the readOnly annotation, the description gives enough scope for a data-fetch tool, though sibling differentiation remains thin.

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% with all 14 params individually documented, so the schema carries the semantics. The description only lists filter categories in prose and adds nothing beyond the schema, matching the baseline 3 for full coverage.

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) and resource (Baseball Savant Extra Bases Run Value / Arm Value leaderboard rows) and enumerates the supported row types (baserunners, fielders, pitchers, team views, league totals). It does not explicitly distinguish this from close siblings like mlb_statcast_arm_value_details or mlb_statcast_fielding_run_value, so an agent must infer the boundary.

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?

Provides one concrete routing tip (use mlb_discovery for exact sort and key_base_out values), which is useful, but gives no guidance on when to pick this leaderboard over the related _details or fielding_run_value siblings. Usage context is implied rather than stated.

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