browser_list_tabs

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

With no annotations, the description carries the full behavioral burden. It does disclose the most likely source of confusion: the 'active' flag means Chrome foregrounding within its own window, not which tab this session is working in, and it states that other sessions' tabs are excluded. It omits anything about ordering or staleness of the list, but for a zero-parameter read this is solid disclosure.

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?

A compact two-sentence block, front-loaded with the scope, then the field list, then the disambiguation of 'active'. Every clause earns its place; nothing is padded.

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?

No output schema exists, so the description must convey the return shape, which it does by naming id, URL, title, and active. Combined with the explicit session-scope exclusion, this is nearly complete for a trivial read; only list ordering/staleness is unaddressed.

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 takes no parameters, so the schema has nothing to document and the baseline of 4 applies. The description correctly adds no parameter noise.

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?

States a specific verb and resource (list tabs) plus the exact scope (tabs this session owns, defined as opened or adopted) and enumerates the returned fields (id, URL, title, active flag). This lets an agent separate it from browser_switch_tab, browser_get_new_tab, and browser_list_frames without opening a schema.

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 the use case (discover which tabs exist in this session) but never states when to prefer it over alternatives like browser_switch_tab or browser_get_new_tab, nor any exclusions beyond the scope note. Usage is inferable but not guided.

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