customerthermometer_add_recipient_to_list

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

With no annotations provided, the description must carry the full burden of behavioral disclosure. It only says 'Add a recipient,' which implies a mutation but does not state whether the call is idempotent, what happens if the email already exists in the list, whether any email is triggered, or what errors might occur. This is insufficient for a write operation without annotation support.

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 zero filler. It efficiently communicates the core action, though it is terse to the point of omitting useful detail. Still, for pure conciseness, it earns a high score.

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 tool with 5 parameters, no output schema, and no annotations, this description is far too thin. It does not explain return values, side effects, error conditions, or the meaning of optional fields, leaving an agent guessing about how to correctly invoke and interpret the tool.

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 only 40% (descriptions for listId and emailAddress only), leaving firstName, lastName, and companyName undocumented. The description does not compensate at all—it mentions none of the parameters or their meanings, so the agent receives no help in understanding the optional fields or their formats.

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 ('Add') and resource ('a recipient to a Customer Thermometer recipient list'), making the tool's core purpose unambiguous. It naturally contrasts with sibling tools like customerthermometer_unsubscribe_recipient, which handle the opposite operation. However, it does not mention the optional fields (firstName, lastName, companyName) that are part of the tool's scope.

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 customerthermometer_unsubscribe_recipient or customerthermometer_get_recipient_lists. There are no mentioned prerequisites (e.g., list must exist), no exclusions, and no context about how this differs from other recipient operations beyond the basic 'add' verb.

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