Set variable initial value

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

No annotations provided, so description carries full burden. It discloses modification of start scene's script, the value constraint (signed 16-bit), and the reason for necessity (no default-value field). Could mention if previous initialization is overwritten, but overall thorough.

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?

Front-loaded with main action, three concise sentences each adding essential information (prerequisite, limitation, alternative). No fluff or repetition.

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 no output schema and only 2 params, description adequately covers all needed context: game-specific use case, prerequisite, alternative tool for different scenarios. No gaps for agent to infer.

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 50% (only variableId described in schema). Description adds meaning: value must fit signed 16-bit range, variable must already exist. Compensates for schema gaps with practical constraints.

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 tool initializes a variable at game start by inserting/updating an event, specifying the resource (variable), context (GB Studio 4.x), and distinguishing from siblings like create_variable (adding new variable) and patch_script (in-game changes).

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?

Explicitly states when to use (game start initialization) and when not to (in-game changes, use patch_script). Also provides prerequisite: variable must exist, so call create_variable first. No ambiguity.

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