List Contact Properties

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

No annotations are provided, so the description carries the full burden. It explains the basic behavior (listing all properties) but does not mention pagination details despite the schema having after/before/limit parameters. This omission could lead to incorrect usage (e.g., assuming all results come in one call).

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 two sentences with no fluff. It front-loads the main purpose and provides actionable instructions without wasting words. Every sentence adds value.

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 tool has 3 parameters (none required) and no output schema. The description covers purpose and usage but does not describe the output format or what fields the response contains. While the schema documents parameters, the lack of output description leaves the agent guessing about the return structure.

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 100%, so the baseline is 3. The tool description does not add additional meaning beyond the schema; it only mentions property IDs in a usage context, not parameter-specific details.

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 it lists all contact properties from Resend, which is a specific verb+resource. It distinguishes from sibling tools like get-contact-property and create-contact-property by explaining its role in getting property IDs and custom attributes.

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?

Explicitly states when to use the tool: 'If you need a contact property ID, you MUST use this tool' and provides guidance on what not to do (avoid volunteering IDs or dates). This gives clear context for agent decision-making.

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