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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds real behavioral context beyond that: results are paginated, and League aggregate detail rows are unavailable. It does not describe pagination limits or the response shape, but the additions are meaningful.

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 short sentences, front-loaded with the primary action and constraint, with the alternative tool named last. No filler and every clause carries information.

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 tool with a full-coverage schema, an output schema, and safety annotations, the description supplies the needed framing: where entity_id comes from, the pagination nature, and the League-aggregate limitation. It could be slightly more explicit about the upstream leaderboard call, but nothing critical is missing.

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 per-parameter meaning is already fully documented and the baseline is 3. The description adds only broad framing ('Pass its entity_id and matching table filters') and the pointer to mlb_discovery, without adding syntax or constraints beyond the schema.

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?

The description states a specific verb ('Fetch'), a specific resource ('paginated pitch-event rows'), and scopes it to a 'Catcher Framing leaderboard entity', which distinguishes it from the sibling leaderboard tool mlb_statcast_catcher_framing and other *_details drill-downs.

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?

It tells the agent to pass entity_id plus matching table filters and explicitly routes to mlb_discovery for exact filter values, and notes that League aggregate details are unavailable. It stops short of saying explicitly 'call this after mlb_statcast_catcher_framing to drill into a row', so context is clear but not fully pinned.

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