Focus Space

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

Annotations cover the safety profile (readOnlyHint=false, idempotentHint=true, destructiveHint=false), and the description adds context annotations cannot express: it blocks until the user stops typing or moving the mouse, and fails with userActive=true if they never pause. That failure mode is exactly what an agent needs to handle this call correctly.

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?

Three short sentences, front-loaded with the action, then the caveat, then the blocking/failure behavior. Every sentence earns its place with no redundancy.

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?

With only one fully documented parameter and no output schema, the description supplies the remaining critical context: the user-visible side effect, the idleness wait, and the userActive failure signal. Nothing an agent needs to invoke this correctly is missing.

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 schema already states the parameter accepts a 'Space id or title from list_spaces.' The description adds no syntax or format detail beyond that, so the baseline 3 applies when the schema does the heavy lifting.

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?

States a specific verb and resource ('Switch the front Arc window to a space') and immediately clarifies the effect on the user's view. This is clearly distinguishable from siblings like list_spaces or switch_to_tab, which operate on tabs rather than spaces.

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 says the tool is 'rarely needed' and why: tabs in an unfocused space remain 'fully readable and scriptable.' That is an unusually strong when-not-to-use statement, effectively steering the agent away from unnecessary calls without naming a competing tool (none exists in the sibling list).

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