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 the useful scope constraint that only the standard board is served and that other categories are excluded, but says nothing about return shape, rate limits, or freshness. With annotations doing the heavy lifting, a 3 is appropriate.

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?

Three sentences, front-loaded with the core purpose, then filters, then the routing caveat. No filler, though the filter enumeration in sentence two partially duplicates what the schema already lists.

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 so return values need no explanation, all nine optional parameters are documented, and annotations cover safety and openness. Scope and sibling routing are stated, leaving little an agent would need that isn't already present.

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% and each parameter already documents its own value set (type values, min_bbe buckets, limit range, team_id source). The description only paraphrases those filters without adding syntax, defaults, or format detail, so the baseline 3 applies.

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 and resource ('Fetch Baseball Savant's standard Statcast leaderboard') and enumerates the row types it covers (batters, pitchers, teams, pitcher teams). The phrase 'standard-board tool' plus the note that other Statcast categories are not covered cleanly separates it from the many mlb_statcast_* siblings.

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 the agent to mlb_discovery for exact filter sets and warns that other Statcast categories are outside this tool's scope, which is real when-to-use/when-not guidance. It stops short of naming which specific sibling leaderboard to use for those other categories, leaving that inference to the agent.

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