Unity API Communicator MCP Server

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

With no annotations provided, the description carries the full burden. It discloses the return format (name, active state, tag, layer, child count) and the hierarchical depth constraint, which are useful behavioral traits. However, it lacks details on permissions, rate limits, or error handling, leaving some gaps for a tool with zero annotation coverage.

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, efficient sentence that front-loads the core purpose and includes all necessary details (action, resource, hierarchy depth, return values) without any wasted words. Every part earns its place.

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 the tool's low complexity (0 parameters, no output schema, no annotations), the description is mostly complete—it covers purpose, behavior, and output format. However, it lacks some contextual details like error cases or performance considerations, which could be beneficial despite the simplicity.

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?

The input schema has 0 parameters with 100% coverage, so the baseline is 3. The description adds value by clarifying that no parameters are needed and implicitly confirming the tool's scope (active scene, 2-level hierarchy), which compensates for the lack of parameters, warranting a higher score.

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 specific action ('List all root GameObjects'), the resource ('in the active scene'), and the scope ('with a 2-level hierarchy'). It distinguishes itself from sibling tools like 'gameobject_hierarchy' by specifying the limited depth and from 'gameobject_find_by_tag' by not filtering.

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 context by specifying 'active scene' and '2-level hierarchy', which helps differentiate it from broader hierarchy tools. However, it does not explicitly state when to use this tool versus alternatives like 'gameobject_hierarchy' or 'selection_get', nor does it mention prerequisites or exclusions.

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