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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions the 'write_mode' requirement, which is helpful, but doesn't describe what happens on success/failure, whether the operation is idempotent, what validation occurs, or how conflicts with existing variables are handled. For a creation tool with zero annotation coverage, this leaves significant behavioral gaps.

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 concise at just two short sentences, with the core purpose stated first and the prerequisite clearly indicated. Every word earns its place with no redundancy or unnecessary elaboration.

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 that this is a creation tool with no annotations, 0% schema description coverage, but with an output schema present, the description provides minimal but functional information. The presence of an output schema means the description doesn't need to explain return values, but it should do more to explain parameters and behavioral context for a tool that creates resources.

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?

With 0% schema description coverage for both parameters, the description provides no information about what 'key' and 'value' represent, their formats, constraints, or examples. The description doesn't compensate for this complete lack of parameter documentation in the schema, leaving the agent with no guidance about what to provide for these required 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 description clearly states the action ('Create') and resource ('new instance variable'), making the purpose immediately understandable. However, it doesn't differentiate this tool from its sibling 'update_variable' or explain what distinguishes 'instance variables' from other variable types in this system.

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 one explicit prerequisite ('Requires write_mode'), which gives some context about when this tool can be used. However, it offers no guidance about when to choose this tool versus 'update_variable' for modifying existing variables or 'create_variable' versus other creation tools like 'create_tag' or 'create_credential'.

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