ff_close_tab

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

With no annotations, the description carries full burden. It mentions prerequisites (bridge add-on) and default behavior (close active tab), but fails to disclose return value, error handling for invalid tabId, or consequences of closing the last tab.

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 concise sentences with no fluff. The key action is front-loaded, and every word adds value.

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 tool with one optional parameter and no output schema, the description covers purpose, parameter semantics, and a dependency. It lacks return value information and differentiation from sibling 'close_tab', but otherwise is adequately complete.

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 0%, but the description explains the 'tabId' parameter as an integer ID with a default of active tab if omitted, adding meaningful context beyond the bare schema. It could further mention how to obtain tab IDs.

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 verb ('Close') and resource ('tab'), specifies it operates on a 'real' Firefox instance, and distinguishes from siblings like 'close_tab' by emphasizing the real browser context and the bridge add-on requirement.

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 context on when to use this tool (for real Firefox tabs with the bridge add-on), but does not explicitly state when not to use it or compare to alternatives like 'close_tab' (likely for virtual browser).

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