List Chrome tabs

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

With no annotations, the description carries the full burden of behavioral disclosure. It only states the scope ('visible to extension') but does not disclose whether the operation is read-only, what the output format looks like (e.g., tab IDs, URLs, titles), or any side effects. An agent cannot infer if this is safe to call repeatedly or what data it returns.

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 a single, front-loaded sentence with no filler. It immediately states the action and scope, and every word adds value. This is a model of conciseness for a simple tool.

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 tool's simplicity (no params, no output schema), the description is somewhat adequate but leaves a key gap: it does not specify what the returned list contains (e.g., tab IDs, URLs, titles). Since there is no output schema, the description should at least hint at the return format for the agent to use the results effectively. Additionally, it could mention common use cases (e.g., enumerating tabs before claiming one) to improve decision-making among many siblings.

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 and the schema has no properties, so there is nothing to describe. Per the baseline for 0-parameter tools, a score of 4 is appropriate since the description is not required to explain parameters. However, it does not add any supplementary detail about parameters because none exist.

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 'List' and the resource 'tabs', and adds useful scope constraints ('visible to the Chrome Browser Control extension', 'current Chrome profile'). This differentiates it from siblings like list_frames (frames vs tabs) and claim_tab/release_tab (management actions). An agent can immediately know the tool's core function without ambiguity.

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 tool is used to enumerate tabs within the extension's visibility, but it does not explicitly state when to use this over alternatives like snapshot, visible_snapshot, or page_status. It lacks guidance on prerequisites (e.g., whether a session must be named) or complementary usage (e.g., before claiming a tab). The context is clear but exclusions are absent.

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