zen_close_tab

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

With no annotations provided, the description fully carries the burden. It clearly indicates the destructive nature (closing a tab) and the important behavioral constraint, but does not detail potential error handling or side effects.

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?

Two sentences with zero redundancy; every word serves a purpose. Ideal conciseness.

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?

Given the simple operation (close tab) and no output schema, the description covers the core functionality and key constraint. Missing details like error handling are minor for this straightforward tool.

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 single parameter 'index' is described with a helpful reference to 'zen_list_pages', adding contextual meaning beyond the schema. Schema coverage is 100%, so the description adds value.

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 action ('Close a tab by index') and the resource ('tab'), effectively distinguishing it from siblings like 'zen_new_tab' and 'zen_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 mentions the constraint 'Cannot close the last remaining tab', providing necessary condition but lacks explicit guidance on when to use this tool versus alternatives like 'zen_select_page' or 'zen_wait'.

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