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

No annotations are provided, so the description carries the full disclosure burden. It explicitly states that the tool navigates back one page and reports the resulting browser location, which is helpful. However, it does not mention edge cases like an empty history or potential side effects (e.g., losing form input), leaving some behavioral ambiguity.

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 that is front-loaded with the action, uses the analogy efficiently, and contains no filler words. Every part contributes to understanding the tool's behavior.

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 zero-parameter tool, the description covers the core action and the reporting behavior. It lacks details about the output format and error conditions, but these are minor for such a simple tool and the description is sufficient for an agent to call it correctly.

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?

With zero parameters and an empty schema, the description does not need to add parameter meaning. The baseline of 4 applies because there are no parameters to explain, and the description adds no unnecessary parameter-related content.

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 uses a specific verb ('go back') and resource ('browser's history'), and the analogy to the back button makes the purpose unambiguous. It is clearly distinguishable from siblings like 'open' or 'probe', which are different navigation actions.

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 phrase 'like the back button' provides clear context for when this tool is appropriate: when the agent needs to emulate a standard browser back action. It does not list exclusions or alternatives, but the simplicity and sibling set make the intended use obvious.

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