List contacts

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

With no annotations, the description carries the full burden for behavioral disclosure. It does not state that this is a read-only operation, any authentication requirements, rate limits, or pagination behavior beyond the schema. It only lists the output fields, which is minimal for full transparency.

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, front-loaded sentence with no redundant words. It efficiently conveys the tool's purpose and return fields.

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 simple list tool with no output schema, the description adequately explains the return values (names, emails, phones). However, it omits details about default page size or that it lists all contacts unless limited, though these are covered in the schema. Overall, sufficient for the tool's complexity.

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 coverage is 100%, with descriptions for both 'account' and 'pageSize'. The description adds no additional meaning to the parameters, though it reaffirms that contacts belong to the account. Baseline 3 is appropriate as the schema already defines each parameter.

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 action (List), resource (contacts), and scope (the account's contacts). It also specifies the returned fields (names, emails, phones), making it distinct from siblings like google_contacts_search and google_contacts_create.

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 vs alternatives such as google_contacts_search. The description does not mention exclusions, prerequisites, or specific scenarios, leaving the choice to the agent without context.

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