new_page

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

Beyond the readOnlyHint false annotation, the description adds only the default URL behavior. It fails to disclose important side effects such as bringing the new tab to focus, background opening, or the isolated context feature, which are relevant for a mutating action.

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 short and front-loaded, with the core action stated first. However, the second sentence is problematic due to contradicting the required URL, so it does not fully earn its place, though the overall structure is concise.

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 four parameters and no output schema, this description is notably incomplete. It lacks information about the return value, the effect on the current page, background handling, and isolated contexts, leaving the agent with insufficient behavioral context.

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 description introduces confusion by suggesting the URL can be omitted ('Use project URL if not specified otherwise'), while the schema marks url as required. This contradictory guidance undermines parameter understanding rather than adding value. No other parameters are addressed.

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 tool's function with a specific verb 'open' and resource 'new tab', and explains the URL loading behavior. This effectively distinguishes it from siblings like navigate_page, which likely operates on the current 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 description implies usage when a new tab is needed, and the project URL fallback provides some context. However, it does not explicitly mention alternatives or when not to use this tool, leaving some ambiguity.

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