create_variable

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

With no annotations, the description partially discloses type_name and address formats, but fails to mention side effects (e.g., duplication errors), triggers (e.g., rebuild), or permission requirements. This is a significant gap for a creation tool.

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?

Description is concise, with key information front-loaded. Every sentence adds value. Could be slightly improved with structured list, but perfectly adequate.

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 5 parameters, no output schema, and no annotations, the description is incomplete. Missing details on error handling, return values, and constraints beyond type_name and address. Leaves many operational questions unanswered.

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 coverage is 0%, and description adds meaning: explains type_name (IEC types, arrays, DDT/DFB) and address (topological address). However, it does not clarify name, comment, or initial_value syntax or constraints, so compensation is partial.

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?

Description clearly states 'Create a global variable' with specific verb and resource. It distinguishes from siblings like update_variable and delete_variable by explicitly focusing on creation. Additional details on type_name and address add precision.

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 explicit guidance on when to use this tool vs alternatives like update_variable or list_variables. The context of 'global variable creation' is implied but there's no mention of prerequisites or exclusions, leaving the agent to infer usage from purpose.

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