Unity API Communicator MCP Server

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

No annotations are provided, so the description carries the full burden. 'Set parent' implies a mutation operation, but it doesn't disclose behavioral traits such as permissions required, whether changes are reversible, effects on child objects, or error handling. The mention of 'POST' hints at a write action but lacks depth needed for a mutation 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 brief and front-loaded with the core action ('Set parent'), followed by technical details (endpoint and category). It avoids unnecessary words, but the lack of meaningful content limits its helpfulness, keeping it from a perfect score.

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 complexity of a mutation tool with no annotations, no output schema, and a nested parameter object, the description is incomplete. It doesn't explain what the tool does beyond the vague 'Set parent', missing details on inputs, outputs, and behavioral context needed for effective use.

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 1 parameter with 100% description coverage, but the schema description defers to the tool description ('Refer to the tool description for expected fields'). The tool description adds no parameter semantics—it doesn't explain what 'params' should contain (e.g., gameobject IDs, parent relationships). Baseline is 3 due to high schema coverage, but the description fails to compensate by clarifying parameter meaning.

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 'Set parent (POST /api/gameobject/hierarchy) [Category: gameobject]' is tautological—it restates the tool name 'gameobject_hierarchy' as 'Set parent' without clarifying what 'parent' means or what resource is being modified. It mentions the HTTP method and endpoint but lacks a specific verb+resource combination that distinguishes it from sibling tools like gameobject_transform or gameobject_active.

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 guidance is provided on when to use this tool versus alternatives. With many sibling tools related to gameobjects (e.g., gameobject_create, gameobject_delete, gameobject_transform), the description fails to indicate context, prerequisites, or exclusions, leaving the agent without usage direction.

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