create_variable

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

With no annotations present, the description carries the full burden of behavioral disclosure, but it only says 'Create a design variable/token.' It doesn't mention required prerequisites, whether existing variables with the same name are overwritten, mode handling, or the fact that this is a mutating operation with no output schema.

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 concise sentence with no filler or redundant detail. It is appropriately front-loaded, though it is arguably too terse given the tool's complexity.

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, a nested object, no output schema, and no annotations, the description is incomplete. It does not mention dependency on a collection, variable type semantics, mode values, or what the tool returns, making it hard for an agent to fully understand the operation without inspecting the schema.

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 schema fully documents the parameters. The description adds no additional meaning beyond 'design variable/token', which only weakly reinforces the purpose of the parameters. Baseline 3 is appropriate because the schema does the heavy lifting.

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 states a clear action ('Create') and a specific resource ('design variable/token'), which distinguishes it from sibling update/delete/get variable tools. However, it could more explicitly differentiate from create_variable_collection, since collections and variables are related concepts and the description uses the broad term 'token'.

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 usage guidance is provided. The description does not state when to use this tool versus create_variable_collection, bind_variable, or create_design_tokens, nor does it mention prerequisites such as an existing collection.

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