Set the project's start scene

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

Discloses that the tool 'preserves every other setting field' and that the sceneId must be valid. Without annotations, the description carries the burden and does so well for a simple mutation, though it lacks details on error handling or return behavior.

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 sentences with no wasted words. First sentence defines action and location; second sentence adds critical constraint. Front-loaded with key information.

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?

Fully covers the tool's behavior for a single-parameter mutation with no output schema. Includes input requirement, consequence, and scope of effect (preserves other fields). No gaps.

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?

Adds significant value beyond the schema. The schema only states 'Must exist in project/scenes/', while the description explains the consequence of invalid input ('build_rom will fail') and the exact file being patched ('project/settings.gbsres').

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?

Clearly states the action ('patch'), resource ('startSceneId in project/settings.gbsres'), and purpose ('so the game boots into the given scene'). Distinguishes from sibling tools like list_scenes or create_scene by specifying a unique mutation operation.

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 that the sceneId must exist on disk and that failure to do so will cause build_rom to fail. Provides context for when to use this tool (to change start scene) but does not explicitly list alternatives or when not to use it.

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