list_contacts

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

With no annotations, the description carries the behavioral disclosure burden. 'List' implies a read-only operation, and the parameter docs clarify pagination and sorting behavior. Still, it does not explicitly state that contacts are not modified, what happens with an invalid or unauthenticated email, or what 'basic information' includes, leaving some behavioral ambiguity.

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 front-loaded with a clear one-line summary and then uses a well-organized Args/Returns structure. It is slightly repetitive of schema defaults and required flags, but overall every section earns its place and the format is easy to parse.

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 definition is adequate for a simple read-only list operation: parameters are documented well and the return type is stated. However, it lacks guidance on when to choose this over 'search_contacts', and with no annotations it does not address authentication assumptions or edge cases, making it incomplete for an agent operating with minimal 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?

Schema description coverage is 0%, so the description compensates fully by explaining all four parameters, including required status, defaults, maximum page size, and the exact allowed values for sort_order. This is exactly the kind of parameter-level detail an agent needs and exceeds what the raw schema provides.

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 a specific verb and resource: 'List contacts for the authenticated user.' This makes the tool's core purpose obvious and distinguishes it from single-contact 'get_contact' or mutating 'manage_contact'. However, it does not explicitly differentiate from the sibling 'search_contacts' tool, so an agent may not know which listing-style tool to prefer.

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 about when to use this tool versus alternatives like 'search_contacts', 'get_contact', or 'manage_contacts_batch'. The description gives context ('authenticated user') but no exclusions, prerequisites, or routing hints. An agent is left to infer usage from the name and parameter list.

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