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

Annotations already mark the tool as read-only, idempotent, and non-destructive. The description adds valuable context beyond annotations: all locations are in Belgium, the head office has bookable=false and cannot be priced, and the type field has a specific meaning. This is useful behavioral and semantic information.

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?

Three dense sentences cover the result contents, the domain-argument relationship, the type distinction, and the bookable edge case. Every sentence earns its place and key usage guidance is front-loaded.

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 zero-parameter reference-list tool with no output schema, the description is complete: it lists the output fields, explains downstream usage, disambiguates from a sibling tool, and flags the unpricable head office. Nothing needed to call or interpret the tool is missing.

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 has zero parameters, so the baseline is 4. The description still adds value by explaining how fields returned here, especially the slug, feed into other tools as arguments.

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 identifies the tool as listing all Floreal Holidays locations in Belgium with a specific set of fields (slug, name, kind, town, region, coordinates). It also distinguishes itself from list_accommodation_types by clarifying that 'type' refers to site kind, not accommodation offerings.

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?

It explicitly tells the agent to use the slug as the `domain` argument for other tools and directs questions about accommodation types to list_accommodation_types. It does not compare itself against every sibling, but the main alternative is clearly named and routed.

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