list_tabs

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

Annotations indicate readOnlyHint: true, which the description reinforces by using 'List.' The description adds workflow context about presenting the list to the user and proactively calling it when unsure, which goes beyond the annotation's minimal information. However, it does not disclose potential ordering or pagination behavior, though for a simple list tool this is minor.

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 sentences. The first sentence states the core function, the second provides usage guidance. Every word earns its place, with no redundancy or fluff.

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 list tool with an output schema and a clear read-only annotation, the description fully covers what the tool does, when to use it, and how to handle the results. It is complete for its simplicity, leaving no significant gaps.

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?

There are zero parameters, so the baseline is 4. The description correctly avoids inventing parameter details, and the schema is empty because no input is needed. No additional parameter semantics are required.

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's function: 'List all open Chrome page tabs with their targetIds, titles, and URLs.' The verb 'List' is specific and the resource ('Chrome page tabs') is unambiguous, distinguishing it from sibling tools like switch_tab or get_title.

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?

Provides explicit when-to-use guidance: 'When you are unsure which tab to inspect, call this proactively to discover available tabs, then present the list to the user and ask which one to switch to.' It also offers an exclusion: 'do NOT tell the user to switch tabs manually in Chrome,' clearly positioning this tool as the alternative to manual user action.

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