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

Beyond the readOnlyHint and openWorldHint annotations, the description discloses that the tool returns 'a verdict plus every step taken' and that the verdict set is three, not two. It also surfaces a concrete failure mode: in soccer, 'involvement' is REQUIRED once the player is in an offside position and 'the call errors without it.'

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?

The description is front-loaded with the most important verdict information, but the 'WHY DELEGATE THIS' paragraph largely repeats the soccer/hockey distinctions already given. The ownership sentence is useful, yet the redundancy could be trimmed without losing value.

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 nine-parameter, two-sport tool with no output schema, the description covers the critical rule branches, the three possible verdicts, sport-specific input semantics, and important exceptions/error conditions. It does not fully describe the output shape beyond 'verdict plus every step taken,' but it is sufficiently complete for an agent to invoke the tool 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 78%, so many parameters are already documented, but the description adds rule-level meaning that helps an agent pick correct values: the armpit boundary, restart exceptions, deliberate play vs deflection, the hockey blue-line plane, and the tag-up exception. It does not walk through every parameter, but it substantially augments 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 opens with a concrete verb and resource: 'Returns a verdict plus every step taken' and immediately names the exact rule sources (IFAB Law 11, NHL Rule 83). It distinguishes the tool's scope across soccer and hockey and explains the three-verdict nuance, so an agent knows precisely what this tool does.

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 'WHY DELEGATE THIS' section explains why this tool exists — the two sports conflate structurally opposite offside rules — and explicitly names the direct Sports Rules endpoint as an alternative, saying it is 'also callable directly if you would rather not go through the aggregator.' It lacks an explicit 'use this when...' statement, but the context and alternative are clear enough for routing.

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