Manage tabs

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

Annotations already indicate readOnlyHint=false and destructiveHint=false, so the safety profile is known. The description adds the important behavioral context that other tools act on the active tab, which influences how tab selections affect subsequent operations. It does not disclose details like what happens to unsaved state on close, but this is not required given 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 two sentences long, front-loaded with the action verbs and followed by the scope-defining sentence. Every word adds value, and there is no redundancy or filler.

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 tool with 4 parameters, no output schema, and clear annotations, the description is mostly complete. It explains the tool's actions and its relationship to other browser tools. The only gaps are the `tabIndex` vs `index` naming inconsistency and the lack of explicit mention that `action` defaults to 'list', though that is in the schema.

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 coverage is 75% (url, index, profileId described; action has enum and default but no description). The description maps 'open' and 'switch' to action values 'new' and 'select', adding some semantic clarity. However, it refers to 'tabIndex' while the schema uses 'index', creating a minor naming inconsistency that could confuse the agent.

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 specific verbs: 'List, open, switch or close tabs.' It also distinguishes the tool from siblings by noting that other browser tools operate on the active tab unless given an explicit `tabIndex`, which establishes its unique role in tab management.

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 clear context for when to use this tool—when managing tabs—and implicitly contrasts it with sibling tools by explaining that other tools act on the active tab. However, it does not explicitly list alternative tools or exclusions, such as using browser_navigate for navigation in the current tab, leaving some ambiguity.

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