Close Browser Tab

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

The description warns that closing a tab discards unsaved in-memory state, which adds value beyond the destructiveHint annotation. It also specifies preconditions to mitigate risks. However, it does not detail the exact consequences (e.g., whether the tab is immediately removed or requires confirmation), so slightly incomplete.

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 concise (three sentences) and front-loaded with the primary use case. Every sentence adds information. However, the term 'full-profile workflow' could be clarified. Overall well-structured.

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 destructive tool, the description covers purpose, preconditions, consequences, and next steps. The presence of an output schema reduces the need to describe return values. Missing: handling of invalid pageId or when no such tab exists. But overall adequate.

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 schema provides no description for pageId. The description implies it is the identifier for the tab to close, but does not explicitly define it or specify how to obtain it (e.g., from list_tabs). This leaves ambiguity.

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 role: 'remove an unneeded page or recover from a page-specific failure.' This distinguishes it from sibling tools like browser_close (which closes the entire browser) and navigation tools. The title reinforces purpose.

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 explicit when-to-use guidance ('Use when a full-profile workflow must remove an unneeded page...') and preconditions about identifying the page and stopping traces. It also gives next steps. This helps the agent decide when to invoke this tool over alternatives.

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