add_to_list

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

The description implies a write operation but does not disclose any behavioral traits such as idempotency, permissions, or side effects. With no annotations, the description should provide more context but fails to do so.

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 concise, consisting of a single sentence with no unnecessary words. It is front-loaded, but could benefit from additional structure to convey more information efficiently.

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 tool with 2 required parameters and no output schema, the description is minimal. It lacks details such as return value or confirmation of operation, making it incomplete for an agent to use effectively.

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?

The parameters 'listUri' and 'actor' are not described in the schema (0% coverage) and the description does not explain their semantics. While names hint at their purpose, it is insufficient for precise invocation.

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 'Add a user to an existing list' clearly states the action (add) and the resources (user and existing list). It distinguishes from sibling tools like 'create_list' and 'remove_from_list' by specifying the operation on an existing list.

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 versus alternatives. There is no mention of prerequisites, constraints, or context for using the tool, leaving the agent without direction.

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