close_tab

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

There are no annotations provided, so the description carries full behavioral disclosure burden. It does well: explains it uses the chrome.tabs.remove extension action, describes the auto-reconnect behavior after closing an active tab (via attach callback syncing active_tab_id), and discloses the ok:false return when no tab is available to close. This is meaningful behavioral context beyond the raw name.

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 compact and information-dense: example call, omission default, underlying mechanism, reconnect behavior, and failure mode all in three sentences. It's front-loaded with the purpose and packs details efficiently without waste.

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 1-param tool with no output schema and no annotations, the description covers purpose, parameter semantics, behavioral side-effects (reconnect after closing active tab), and failure signaling (ok:false). This is reasonably complete for the complexity level.

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% (the tab parameter has no description in the schema), so the description must compensate. It explains the example value (123) and the omission behavior, but doesn't elaborate on parameter constraints (e.g., whether negative/invalid ids produce specific errors). The description provides baseline value but doesn't fully compensate for zero schema coverage.

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 closes a specified tab with example usage 'close_tab(123)'. It distinguishes itself from siblings like switch_tab and new_tab by the verb '关掉' (close) + resource (tab). However, it doesn't explicitly differentiate from other tab-related tools beyond the clear 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 implies usage context (closing a tab, defaulting to current attached tab if omitted) but provides no explicit when-to-use vs alternatives guidance. It does explain the tab-omission behavior clearly, which is useful context for an optional-parameter tool.

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