playwright__browser_tabs

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

Annotations already mark destructiveHint=true and readOnlyHint=false, so the description's 'create, close' is consistent but adds no new behavioral insight. It does not disclose error handling (e.g., what happens if you close a non-existent tab), side effects of 'select' (focus changes), or the fact that openWorldHint=true implies external side effects. The description is too minimal to add value beyond the annotations.

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 sentence, which is very concise and front-loaded. It lists the actions without any filler. However, it could be more structured (e.g., bullet points) to improve readability, but it is not wasteful.

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 no output schema, the description should explain what the tool returns for each action (e.g., for 'list', a list of tabs; for 'new', the new tab's info). It does not do this. Additionally, the description does not mention the tool's scope (e.g., operates on the current browser context). The tool has multiple actions and no output documentation, making it incomplete.

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 100%, so the schema already documents each parameter (url, index, action). The description does not add any extra meaning or clarify usage of the parameters beyond what the schema provides. Baseline 3 is appropriate.

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 specific verb-resource combination: 'List, create, close, or select a browser tab.' This directly addresses the four distinct actions the tool performs, and it distinguishes the tool from sibling tools like playwright__browser_navigate (which navigates the current tab) and playwright__browser_close (which closes the entire browser).

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 provides no guidance on when to use this tool versus alternatives. It does not mention that for navigating the current page one should use playwright__browser_navigate, or that closing the browser should use playwright__browser_close. The actions are listed but without context of trade-offs or prerequisites.

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