browser_tabs

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

Annotations already declare readOnlyHint=false and destructiveHint=true, covering the safety profile. The description adds the action list but this is redundant with the schema enum. It doesn't disclose additional behaviors such as what 'close' with omitted index does (though schema notes it) or effects of 'select'. With annotations present, the description provides minimal extra value, warranting a 3.

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, 'List, create, close, or select a browser tab,' which is extremely concise and front-loaded. Every word contributes to the core function. There is no filler or repetition.

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?

This is a multi-action tool with no output schema, yet the description does not explain return values (e.g., what 'list' returns) or when each action is appropriate. It lacks essential context for an agent to fully understand the tool's capabilities beyond the action names. The schema covers parameters but not behavioral outcomes, leaving the description insufficiently complete.

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% with each parameter (url, index, action) described. The description adds no parameter-level detail beyond the schema, so it neither enhances nor detracts. Baseline 3 is appropriate for full schema coverage.

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 manages browser tabs with four specific actions (list, create, close, select), matching the schema enum. It identifies the resource (browser tab) and action verbs, making the purpose unambiguous. It doesn't explicitly contrast with sibling tools like browser_close or browser_navigate, so it's not a 5.

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 doesn't mention scenarios like 'use for tab-level operations instead of browser_close' or any prerequisites. Merely listing actions implies usage but provides no exclusions or comparative context, which falls short for a tool with many siblings.

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