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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered by structured data. The description still adds real behavioral context: the result is scoped to the caller only, and the federation snapshot is conditional ('when there is one'), which tells the agent to expect a sometimes-absent field. The trailing 'Read-only' merely restates the annotation, which keeps it from a 5.

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?

Front-loaded with what is returned, then routing, then the scope caveat — a sensible order for an agent scanning quickly. Nearly every clause earns its place; only the closing 'Read-only' is wasted because the annotations already say so.

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?

There is no output schema, so the description carries the burden of describing the return, and it does: handicap index, its source, and an optional federation snapshot. Combined with the sibling routing and the zero-parameter schema, an agent has everything needed to call this 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?

The tool takes zero parameters, so there is no parameter meaning to add and the baseline applies. The description correctly spends its words on what the call returns rather than inventing parameter guidance.

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 (read) and resource (the player's own handicap index) plus the two sub-values returned, its source and the federation snapshot. It explicitly carves itself out from the handicap siblings, so an agent can separate it from project_handicap and playing_handicap without opening a 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?

Gives explicit routing: 'Use it for the current number; to explain or project it use project_handicap, and for a course or playing handicap use playing_handicap.' Each alternative is named with the condition that selects it, and the 'never returns another player's handicap' line rules out the scope an agent might otherwise assume.

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