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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds useful operational context (local table sort, discovery lookup for exact filter values, expandable player rows) but says nothing about pagination limits beyond the schema or any rate/cost behavior.

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 compact sentences, front-loaded with the core action, with the routing hints appended. Dense but every clause carries information; only mild cramming of many filter names into one sentence.

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 an output schema present, return values need not be explained, and the description covers filtering, discovery lookups, and the details-expansion path for a 10-parameter all-optional tool. The main gap is the unresolved overlap with the plural sibling tool.

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 each of the 10 parameters is already documented with defaults and allowed values. The description merely enumerates the filter categories, adding no syntax or semantics beyond the schema — the correct baseline of 3.

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 Pitch Arsenal Stats for pitchers or batters'), making the domain and the pitcher/batter axis clear. It does not differentiate itself from the near-identical sibling 'mlb_statcast_pitch_arsenals' (plural), which an agent could easily confuse, so it falls short of 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?

Gives explicit routing guidance: 'use mlb_discovery for exact values' for filter tokens and 'Player rows can be expanded with mlb_statcast_pitch_arsenal_details'. This is real when-to-use context, though there is no exclusion or guidance about when to prefer the plural sibling instead.

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