list_custom_hostnames

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

Annotations already declare readOnlyHint=true and openWorldHint=true. The description simply states 'List' which is consistent, but adds no additional behavioral traits such as handling of pagination, rate limits, or potential side effects. It does not go beyond the annotations.

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?

The description is a single concise sentence that is front-loaded with the main action. It is efficient, but slightly underspecified given the tool's complexity (5 parameters). However, there is no redundancy.

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?

The tool has 5 parameters, no output schema, and moderate complexity. The description is minimal and does not explain pagination behavior, filtering, or response format. It lacks completeness for an agent to fully understand the tool's behavior.

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 input schema has 60% descriptions coverage (zone_id, hostname, fetch_all described; page and per_page lack). The description itself provides no extra detail about parameters. It does not compensate for the undocumented parameters.

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 states the tool lists custom hostnames (SSL for SaaS) on a zone. It uses a specific verb 'List' and resource 'custom hostnames', distinguishing it from sibling tools like create_custom_hostname or delete_custom_hostname.

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 description does not provide any guidance on when to use this tool versus alternatives. It only describes what it does, without specifying context, prerequisites, or when not to use it. Sibling tools include other list tools, but no differentiation is offered.

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