contacts_list

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

No annotations are provided, so description must convey behavior. It mentions single round trip but omits details on pagination, sorting, or safety. However, it is a read operation, and the description covers parameter effects.

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?

Description is concise: first line states purpose, second line implementation note, then parameter list. No redundant information.

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?

Given the tool's simplicity and existence of output schema, the description is fairly complete. However, it lacks mention of pagination or default limit behavior, and does not address how it differs from contacts_query_contacts.

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 has 0% description coverage, so description compensates by clearly explaining each parameter: address_book_id restricts to a book, text is full-text search, limit is max count. This adds significant value.

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?

Description states 'List contacts' with optional filters, clearly indicating the action and resource. However, it does not differentiate from sibling 'contacts_query_contacts' which may have similar functionality.

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 explicit guidance on when to use this tool versus alternatives like contacts_query_contacts. Usage is implied only for listing contacts with basic filters.

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