browser_switch_tab

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

With no annotations provided, the description carries the full behavioral burden, yet it omits the single most important detail: whether tab_index is 0-based or 1-based, and what happens when the index is out of range or the tab is closed. It also doesn't state that this mutates the browser's active-tab state (a side effect an agent should know about).

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?

A single front-loaded sentence with no filler; the verb and target are immediately clear. It is efficient, though its brevity borders on under-specification for a state-mutating tool.

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?

An output schema exists so return values need not be explained, and there are no nested objects. But for a 1-required-parameter mutation tool with zero annotation coverage, the description should cover index base, invalid-index behavior, and the browser_tabs/browser_focus relationship — none of which appear.

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% for the one required parameter, so the description must compensate — but 'tab index' merely restates the parameter name. It adds no indexing base, no valid range, and no hint about how indices are obtained (e.g., from browser_tabs).

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 plus resource ('Switch active focus to a specific tab index'), which is clearer than a bare 'switch tab' and partially distinguishes it from the similarly named sibling browser_focus by scoping it to tabs. However, it never clarifies how it differs from browser_focus or browser_new_tab, leaving an agent to guess which of the two focus-related tools applies.

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 when-to-use guidance at all — nothing about needing a tab to already exist, about calling browser_tabs first to enumerate indices, or about how this relates to browser_focus. The agent is left to infer the invocation context entirely.

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