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 that results can be grouped, sorted locally, and paginated, and that discovery supplies valid values, but says nothing about rate limits, freshness, or response shape. Adds some value over the annotations, no contradiction.

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 resource and entity scope, then the filter inventory. Efficient and readable, though the long comma-separated filter list is dense.

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 an 18-param read-only query tool with a full output schema and clear annotations, the description covers scope, filters, and the discovery dependency. An agent could call it correctly; only the within-tool ranking of entity types versus other statcast endpoints is left implicit.

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 18 params fully documented including enum-like value lists (knee_code, pitch_types, min_pitches). The description only names the filter categories, which the schema already carries in more detail, so the baseline 3 for high coverage 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) and resource (Baseball Savant Catcher Stance rows) and enumerates the entity types it can return (catchers, catching teams, batters, batting teams, pitchers, league totals). This clearly separates it from sibling tools like mlb_statcast_catcher_framing or catcher_blocking, though it never names an alternative explicitly.

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 a concrete usage context: the filter axes available and a pointer to mlb_discovery for exact enumeration values. It does not say when NOT to use this tool or which sibling to prefer, but the filter inventory and discovery pointer provide actionable guidance.

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