Set Active Instance

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

With no annotations beyond title, the description carries the burden. It discloses input constraints (port number for stdio only) but fails to mention potential side effects, required permissions, or what happens if the target instance is not found. The presence of an output schema mitigates some need for return value explanation.

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 only: first states purpose, second details input formats. No unnecessary words, well-structured for quick comprehension.

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 low complexity (single parameter, no enums, output schema present), the description is adequate. It covers purpose and input formats, though it lacks mention of error behavior or return value specifics (possibly covered by output schema).

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 100% and the parameter description in the schema matches the tool description. The description adds no new semantic meaning beyond what the schema provides, so baseline 3 is appropriate.

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 ('Set the active Unity instance') and the scope ('for this client/session'). It distinguishes itself from sibling tools which manage different aspects of Unity (e.g., managing scenes, assets, editor).

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 explains the accepted input formats (Name@hash, hash prefix, or port number for stdio) which guides usage. However, it does not explicitly state when to use or not use this tool, nor does it mention alternatives, but with no direct sibling conflict this is less critical.

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