contacts_list

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

No annotations are provided, so the description must bear the full burden of behavioral disclosure. It does not mention any side effects, pagination behavior (despite the 'limit' parameter), return structure, or required permissions. The description is minimal, stating only the basic function.

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 succinct with two sentences, no filler or repetition. It efficiently conveys the core function and one parameter. However, it could be more structured by explicitly listing parameters or usage notes.

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 lack of annotations and output schema, the description is incomplete for an agent to use effectively. It does not specify what fields are returned, ordering, or pagination limits. The description covers only the basic operation and one filter, missing critical context for correct invocation.

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 0%, so the description must compensate. It explains the 'missing_email' parameter ('Optionally return only contacts missing an email address'). However, it does not explain the 'limit' parameter or its default/maximum values, leaving the agent without context for pagination.

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 'List contacts' specifying the verb and resource. It also mentions an optional filter for missing email, which adds specificity. However, it does not differentiate from the sibling tool 'contacts_search', which also lists or searches contacts.

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?

There is no guidance on when to use this tool versus alternatives like 'contacts_search' or 'contacts_get'. The usage is implied only through the description of the listing and optional filter, but no exclusions or context are provided.

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