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 result is exactly the 30 clubs with league/division/venue/abbreviation, which is useful payload context, but it discloses nothing further about auth, rate limits, or edge cases (e.g., missing seasons). Adequate given the annotation coverage.

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 with no waste: the payload is front-loaded, and the disambiguation follows immediately. Every sentence 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?

An output schema exists, so return values need not be spelled out, and the description covers purpose, scope, and routing. It is complete for a simple read-only list tool, with only minor behavioral detail absent.

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 coverage is 100% and the schema already explains season as an optional four-digit year defaulting to the current year. The description's 'for a season' only echoes this, adding no syntax or format detail beyond the schema, 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 (Returns), resource (MLB clubs), scope (the 30 clubs for a season), and the metadata fields included. It explicitly names the sibling it is not (mlb_team_roster), so an agent can distinguish this team-list tool from the roster tool without opening either schema.

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?

The second sentence routes the agent to mlb_team_roster when a roster is wanted, giving a clear alternative. There is no explicit 'when to use this one' condition beyond that contrast, but the differentiation is strong enough that selection is unambiguous.

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