Look up a player matchup for one week

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

With no annotations, the description carries the burden. It clearly implies a read-only lookup ('Who a player faces...') and describes the output content. It doesn't mention errors or edge cases, but for a simple lookup tool this is adequate. It is not misleading and adds context beyond the name.

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 filler. The first sentence describes the output, the second prescribes usage. Information is front-loaded and every word 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 lookup tool without output schema, the description covers the purpose, usage context, and key data points. It doesn't state return format or handle edge cases, but given the simple scope and absence of annotations, it is reasonably complete for an agent to invoke correctly.

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%, so the schema already documents all three parameters (player, week, scoring_format). The description does not add new parameter-level meaning beyond what the schema provides—it focuses on output details. Baseline of 3 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?

The description clearly states the resource (player matchup for a given week of the 2026 season), the specific information provided (home/away, opponent generosity), and explicitly contrasts with season-long tools. This distinguishes it from siblings and makes its purpose unambiguous.

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 states when to use: 'for in-season start or sit questions that name a week', and when not to: 'which the season-long tools cannot answer'. This provides direct guidance on tool selection, referencing the limitation of alternatives.

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