Open a URL

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

With no annotations, the description carries the full behavioral burden and does very little with it. It does not disclose what happens to an already-open page, whether the call blocks until load, whether it steals window focus, or what it returns; only the tab default is stated, which is really a parameter fact.

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 wasted words, and the tab-behavior detail is placed immediately after the core action. It is efficient, though the brevity is partly what leaves the behavioral and sibling-differentiation gaps.

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 simple two-parameter tool with no output schema, this is roughly the minimum needed to invoke it. It is still missing the distinction from browser_navigate and any indication of what the call produces or how it affects the current page state.

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 both parameters are undocumented in structured data. The description compensates for new_tab by naming the default and the alternative ('new tab (default) or the current one'), but it adds nothing about url beyond the obvious, so it only partially closes the gap.

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: 'Open a URL in the browser', which is unambiguous on its own. However, it does not differentiate itself from the sibling browser_navigate, which plausibly also opens/navigates URLs, so an agent cannot tell how the two differ from this text alone.

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 implies the invocation choice by explaining that a new tab is the default and the current tab is the alternative, which is a conditional usage hint. It names no sibling alternative (e.g. browser_navigate) and gives no when-not-to-use guidance, so guidance remains implied rather than explicit.

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