create_variable

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 discloses the optional per-mode seeding and color format, but does not mention side effects, return value, permissions, or behavior if the variable already exists. For a mutating operation, this is insufficient transparency.

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?

Two concise sentences, front-loaded with the primary action and followed by essential parameter guidance. Every sentence earns its place with no wasted words.

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?

Schema covers parameter semantics well, and the description provides necessary usage context. However, with no annotations and no output schema, the agent is left without information about return values or error conditions, making it moderately complete for a creation 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 covers all parameters, so baseline is 3. The description adds value by explaining 'per-mode values' as the purpose of valuesByMode and directing the agent to get modeIds from specific tools, which is beyond the schema's generic 'Map of modeId -> value'.

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 and resource: 'Create a variable inside a collection'. It differentiates from sibling tools like create_variable_collection (which creates a collection) and get_variables (which retrieves modeIds).

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?

Provides clear usage context by instructing to get modeIds from get_variables or create_variable_collection, which is essential when using valuesByMode. It implies this is the tool for creating variables but does not explicitly contrast with alternatives.

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