tab_focus

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

The annotations already declare the mutation profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), so the safety bar is lower. The description adds the useful non-obvious fact that this changes the user's visible view, but says nothing about failure when the tab id is invalid or unknown, which is the main behavioral risk.

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?

One sentence, front-loaded with the verb and resource, with the example folded inline. Nothing is wasted and nothing is buried.

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 one parameter and an output schema present, return values need no explanation, and the id example covers the main input gap. Still missing is how to obtain valid tab ids (presumably tab_list) and what happens on an unknown id, which matters for a UI-mutating call.

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 description coverage is 0%, so the description carries the burden. It compensates well for a single parameter by giving a concrete identifier example ("w1:t2"), which is exactly what the bare 'tab_id: string' schema lacks.

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?

Specific verb+resource: "Switch the user's view to a tab" tells the agent exactly what the call does, with an example identifier format. It does not distinguish itself from other focus-like siblings (workspace_focus, agent_focus), but the resource name 'tab' does most of that work implicitly.

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?

There is no guidance on when to use this versus workspace_focus, agent_focus, or tab_list, and no stated prerequisites (e.g., that the tab must already exist). The only contextual hint is 'the user's view', which implies a UI-facing operation.

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