Add user variable

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

The description discloses only the vtype mapping and a cross-reference. It does not mention side effects (e.g., duplicate handling), authorization needs, or any behavioral traits beyond the annotations, which are minimal.

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 extremely short (two fragments), which is concise but lacks structure. It could be better organized as a proper sentence with clearer specification.

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 tool's simplicity, the description is too sparse. It fails to explain the operation's effect, expected return, or any special conditions. The cross-reference is not explained, leaving gaps for an agent.

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 baseline is 3. The description redundantly restates the vtype enum mapping already present in the schema, adding no new semantic value for the parameters.

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 title 'Add user variable' and description 'Add var' clearly indicate the action, though the description is terse and could be more explicit. The sibling tools (update, delete) help disambiguate, making the purpose clear overall.

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?

The description provides no guidance on when to use this tool versus update_user_variable or delete_user_variable. It only offers a vtype mapping, so an agent lacks context for decision-making.

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