list_contacts

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

With no annotations, the description carries the full burden of behavioral disclosure. It states the core behavior ('List contacts') and implies pagination through per_page and page, but adds no extra context (e.g., read-only nature, sorting, rate limits, or what fields are returned). This is adequate but not rich.

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 extremely concise, placing the main function in the first sentence followed by a clear Arg list. Every sentence or phrase adds value, with no fluff or repetition.

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 4-parameter, all-optional list tool with an output schema, the description covers all parameter semantics and the core action. It does not detail return values (output schema exists) but lacks any mention of alternative tools or edge cases, which slightly reduces completeness in the broader tool context.

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 no descriptions (0% coverage), so the description's parameter explanations are essential. It adds meaning beyond the schema by explaining record_type values ('person', 'company', 'all'), keyword search scope ('name, email, etc.'), and pagination semantics ('default 30', 'starts at 1'). This compensates well for the schema gap.

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's function with a specific verb and resource: 'List contacts with optional keyword search.' It distinguishes from get_contact (single contact) and get_contacts_by_ids (specific IDs) but does not explicitly differentiate from the sibling tool search_contacts, so it is not a full 5.

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?

No guidance is provided on when to use this tool versus alternatives such as search_contacts or list_contact_ids. The description only explains parameters, with no exclusions, prerequisites, or explicit usage scenarios, leaving the agent to infer.

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