browser_tabs

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

With no annotations, the description carries the full burden. It clearly indicates a read-only 'list' operation and discloses the exact data returned (index, url, title, active status). It does not explicitly state the absence of side effects, but the verb 'list' strongly implies no mutation, which is sufficient for a simple tool.

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, front-loaded sentence. Every element is useful: the verb, the resource, and the parenthetical list of return fields. No wasted words.

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?

Given the tool's simplicity (no parameters, no output schema, no annotations), the description completely covers what an agent needs to know: what the tool does and what information it will receive. It is self-contained and sufficient for selection and invocation.

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 tool has zero parameters, so the baseline is 4. The description adds value by explaining the output shape, which is the most relevant information for invocation and interpretation.

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 clearly states the verb ('List') and resource ('open tabs'), and adds specificity by enumerating the included fields (index, url, title, active). This unambiguously distinguishes it from sibling tools like browser_new_tab, browser_switch_tab, and browser_close_tab.

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 usage is implied by the name and description: it lists tabs so an agent can see what's open and which is active. However, it does not explicitly state when to use this over alternatives, nor does it note that the returned index can be used with browser_switch_tab or browser_close_tab. This is minimal viable guidance but leaves the agent to infer the use case.

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