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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description adds genuine value beyond that by disclosing the reference content returned — including subjective judgement content like 'what each suits' and 'whether it takes heavy waste' — which tells the agent this is a static reference lookup rather than a live quote.

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?

One sentence, front-loaded with the size range before the list of attributes. Every clause names a distinct piece of returned content; nothing is redundant and nothing restates the tool name.

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 conveying return values, and it does so by listing the five fields per skip size. Minor gaps remain — it does not say how many sizes are covered or whether results are a fixed table versus queryable — but for a no-parameter reference tool this is close to sufficient.

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 the baseline is 4. The description correctly implies no input is required by framing the tool as a fixed catalogue of standard UK skip sizes, consistent with the empty input 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 names the exact resource — standard UK skip sizes from 2 yard mini to 12 yard maxi — and enumerates what each entry contains (dimensions in metres, bag count, suitability, placement, heavy-waste capability). That content profile clearly separates it from siblings like skip_prices, town_skip_facts and how_to_book, so an agent can identify it without opening the 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?

Usage is only implied: an agent can infer this is the lookup for skip sizing questions, but there is no explicit when-to-use statement, no when-not-to-use condition, and no named alternative (e.g. skip_prices for cost questions). The implied scope is clear enough to act on, but routing guidance is left to inference.

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