Set a GDevelop global variable

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

Annotations already indicate the operation is not read-only and not destructive. The description adds context about 'create or update' behavior and value types, but does not disclose details like overwriting existing variables or potential side effects. It covers the basics without contradicting annotations.

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 sentence with no redundant words. It is front-loaded with the action and resource, making it easy to scan.

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 simple setter tool with clear annotations and no output schema, the description is sufficient. It covers the essential purpose and value types. Minor missing details like explicit overwrite behavior are implied by 'update', so the description is adequately complete for its complexity.

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 0%, so the description must compensate. It mentions 'primitive, structure, or array value' which maps to the 'value' parameter, but does not explain 'projectId' or 'name' semantics beyond what the schema types and tool name suggest. It partially compensates for the low coverage, but not fully.

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 or update') and the resource ('editable project-wide variable'), with explicit mention of supported value types ('primitive, structure, or array value'). The term 'project-wide' distinguishes it from sibling tools like set_scene_variable, which target scene variables.

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 implies usage for global (project-wide) variables versus scene variables through the word 'project-wide', but it does not explicitly mention alternatives or exclusions. It provides clear context but no direct comparison with sibling tools, so a score of 4 is appropriate.

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