nex_browser_tab_select

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

No annotations are provided, so the description carries the full behavioral burden. It implies a state change (selecting/focusing a tab) but does not say whether the page must be open, what happens if pageId is unknown, or whether the active session is affected.

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 front-loaded sentence with zero filler. It is appropriately short, though the brevity leaves room for additional clarifying context without becoming bloated.

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 browser-state mutation tool with no annotations, no output schema, and a required parameter undocumented in the schema, the description is too thin. It does not cover return behavior, error conditions, or prerequisites such as obtaining a valid pageId from tab_list.

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 50%: sessionId is documented in the schema, while pageId has no schema description. The phrase 'stable page ID' usefully clarifies that pageId is an identifier rather than an index, but the description does not explain how to obtain it or what 'stable' means in practice.

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 ('Select a tab') and adds the key constraint that selection is by stable page ID. It is distinguishable from tab_list, tab_new, and tab_close by verb, though it does not explicitly name siblings or contrast behavior.

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 gives no guidance on when to use this versus nex_browser_tab_list or nex_browser_tab_new, nor does it say where a pageId should come from. An agent can infer that a tab must already exist, but that is not stated.

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