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

With no annotations, the description carries the load and does well: it discloses the rounding rule, the WHS table used for fewer than 20 scores, and explicitly bounds scope with 'no caps, playing conditions adjustment or exceptional score reduction', which prevents over-trusting the result. It doesn't discuss error behaviour for missing/mismatched parameters, which keeps it below 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 the domain scope, then inputs, then outputs, in one dense paragraph with no filler sentences. The long parenthetical allowance list makes sentences heavy, but every clause carries information an agent would otherwise have to guess.

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 6-parameter, all-optional, annotation-free tool with no output schema, the description covers inputs, both calculation modes, the return value ('the working and a link') and the accuracy caveats. The one gap is that all parameters are optional yet no guidance is given on what a call with no usable inputs returns.

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 baseline is 3, but the description genuinely adds meaning the schema lacks: the format-to-allowance mapping (95% singles stroke play/stableford, 85% fourball better ball, 100% singles matchplay, 90% fourball matchplay, 50% foursomes) and the course-handicap formula tying index, slope, rating and par together. The 'most recent first' ordering is repeated from the schema but the rest is additive.

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 domain (World Handicap System), the exact resources computed (handicap index, course handicap, playing handicap) and the region scoped (UK golfers). Its purpose is unmistakable against the all-price/search sibling set, none of which overlap.

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 two input modes are clearly spelled out: score_differentials for an index, and/or handicap_index with slope_rating, course_rating and par for course/playing handicap. There are no sibling alternatives to route between, so no exclusion guidance is needed, though it doesn't say what happens if neither mode's inputs are supplied.

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