set_active_studio

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

With no annotations, the description carries the full burden. It discloses the state-changing nature ('switches active MCP focus') and requires a 'specific running Studio instance', which is a useful precondition. It does not mention error behavior, whether the previous focus is lost, or whether the switch is persistent, so some behavioral transparency is missing.

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 sentence with no redundant mechanical detail. The 'Official Roblox Studio' prefix adds branding context but is not strictly operational; otherwise, every part of the sentence contributes to the meaning.

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?

For a one-parameter tool with no output schema, the description is largely complete: it names the target resource, the selection identifiers, and the precondition that the instance must be running. It does not explicitly connect to list_roblox_studios for discovering valid IDs, but that is a minor gap given the low complexity.

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 already fully documents studioId at 100% coverage, providing the baseline of 3. The description adds value by clarifying that the identifier can be a ProcessId or PlaceId, which is more specific than the schema's vague 'Process ID or unique identifier'.

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 states a specific verb and resource: it switches the active MCP focus to a running Studio instance, and identifies the selection mechanism (ProcessId or PlaceId). This clearly distinguishes it from siblings like list_roblox_studios, which enumerates instances rather than changing focus.

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 behavior itself implies usage: when multiple Studio instances are running and a specific one must receive subsequent MCP operations, this tool selects it. However, it does not explicitly state when to use this tool versus alternatives such as list_roblox_studios or get_studio_state, nor does it describe prerequisites like how to obtain a valid studioId.

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