get_contacts

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

The readOnlyHint and openWorldHint annotations already cover the read-only and externally-changing nature of the data. The description adds the 'account contacts' context and the exact endpoint name, but does not describe response format, ordering, or any other behavioral details. There is no contradiction with 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 short sentence that front-loads the purpose and adds only the relevant endpoint identifier. There is no filler or redundant explanation.

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 no-parameter, read-only list operation, the description gives enough information for an agent to invoke it correctly: call it and get the account's additional contacts. No input setup, prerequisites, or complex return handling are needed, and annotations cover the safety profile.

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 schema coverage is trivially 100% and the description has nothing to add. Per the baseline for zero-parameter tools, this is adequate.

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 uses a clear action ('list') and a specific resource ('additional contacts of the account'), and the parenthetical endpoint 'whmcs/get_contacts' pins down the exact API. Among siblings like add_contact, update_contact, and delete_contact, it unambiguously identifies this as the read-only list tool.

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 verb 'list' implies the tool is for retrieving contact data, which gives basic usage context. However, it does not explicitly say when to prefer this over sibling contact tools or state that mutations should use add_contact/update_contact/delete_contact.

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