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

The readOnlyHint annotation already establishes this as a safe, non-mutating read, so the description's burden is low. It usefully discloses the shape of each returned record (services, targets, health status), which annotations do not cover. It still says nothing about pagination behavior, default page size, or how large result sets are returned.

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?

Two short sentences, front-loaded with the action and the returned data. The trailing 'Hetzner Cloud: GET /load_balancers' is a compact API reference that earns its place for grounding, with no filler text.

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 simple read-only list tool with no output schema, the description covers the action and the returned fields, and the schema covers all filters and paging. The only real gap is the lack of disambiguation from hetzner_get_load_balancers and unknown paging defaults.

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 description coverage is 100%, so all four parameters (name, page, per_page, label_selector) are already fully documented in the schema, including the label selector syntax. The description adds no parameter-level detail beyond that, making the baseline 3 correct.

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 states a specific verb and resource ('List load balancers') and even enumerates what each entry contains (services, targets, health status), so the agent knows what it is getting back. It does not, however, distinguish itself from the sibling hetzner_get_load_balancers, which an agent could easily confuse with a pure list call.

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?

There is no when-to-use statement, no mention of the filtering parameters, and no routing against hetzner_get_load_balancers (singular fetch) or other list_* siblings. Usage is only weakly inferable from the word 'List' and the presence of name/label_selector params.

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