tab_status

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

With no annotations provided, the description carries the behavioral disclosure burden. It honestly states the data is cached, implying it may not be perfectly live, and characterizes the call as cheap, signaling low cost. It also mentions errors are included, giving useful behavioral context beyond a simple 'get status' phrasing.

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 deliver a dense but readable description: what the tool returns, the typical use case, and a clear boundary. Every phrase earns its place, and the most important identifying information is front-loaded.

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 with no output schema, the description is complete: it lists the returned fields (URL, title, ready state, errors), the scope (active tab), the performance profile (cheap), and the appropriate use case. Nothing essential is missing for an agent to decide whether and when to invoke it.

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 tool has zero parameters, so there is no parameter semantics burden on the description. The baseline of 4 applies because no parameter documentation is needed and the description appropriately focuses on what the tool returns rather than input details.

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 identifies the tool as returning the active tab's cached URL, title, ready state, and errors, which is a specific, concrete resource. It also explicitly distinguishes itself from tools for tab discovery or page content, preventing confusion with siblings like switch_tab, view_page, or dom_snapshot.

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 gives a clear when-to-use scenario: a cheap mid-workflow sanity check, exemplified by 'did my click navigate?'. It also provides an explicit when-not-to-use boundary (not for tab discovery or page content), though it does not name specific alternative tools.

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