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 the output is game-level play records, but says nothing about pagination, row limits, or freshness. With annotations carrying the safety burden, 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?

Two tight sentences, zero waste, with the resource and scope front-loaded and the prerequisite tool named second. Every clause earns its place.

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 10-parameter read tool with an output schema and safety annotations, the description covers what it returns and how to source the required entity_id. It is nearly complete, with only minor gaps around result size/pagination that the output schema may already address.

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 all ten parameters (type, split, team_id, year ranges, key_base_out, minimum_opps, etc.) are already documented in the schema. The description's reference to 'Run, Fld, or Pit' merely echoes the type field and adds no syntax or format detail beyond the schema. Baseline 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 (Fetch) and resource (game-level play records), and scopes it precisely to a Run, Fld, or Pit player row from the Baseball Savant Arm Value leaderboard. This clearly separates it from the sibling mlb_statcast_arm_value, which surfaces the leaderboard itself.

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: 'Use mlb_statcast_arm_value to find eligible rows,' which tells the caller how to obtain the required entity_id. It gives clear usage context but no explicit when-not condition or other alternatives.

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