back

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

With no annotations provided, the description carries the full burden of behavioral disclosure but offers minimal information. 'Navigate back' implies a navigation action but doesn't specify what gets navigated, whether this requires specific browser state, what happens if there's no history to go back to, or what the expected outcome is. For a navigation tool with zero annotation coverage, this is inadequate.

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 extremely concise at just two words. While it may be under-specified, it's not verbose or poorly structured - every word serves a purpose in conveying the core action.

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 navigation tool with no annotations, no output schema, and a completely undocumented parameter, the description is completely inadequate. It doesn't explain what 'back' means in this context, what resource it operates on, what the parameter does, or what the expected outcome is. The description fails to provide the necessary context for an agent to use this tool effectively.

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 has 1 parameter (tabId) with 0% description coverage, meaning the parameter is completely undocumented in the schema. The description 'Navigate back' provides no information about parameters, their purpose, or how they relate to the navigation action. The description doesn't compensate for the schema's lack of parameter documentation.

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 'Navigate back' is a tautology that essentially restates the tool name 'back' with a synonym. While it suggests navigation functionality, it doesn't specify what resource is being navigated (browser history, application state, etc.) or distinguish this from sibling navigation tools like 'forward' or 'navigate'.

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 about when to use this tool versus alternatives. There are multiple navigation-related sibling tools (forward, navigate, reload, get_current_url), but the description offers no context about when 'back' is appropriate versus these other options or any prerequisites for its use.

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