arc_list_tabs

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

No annotations are provided, so the description must disclose behavioral traits. It only states 'list all open tabs' but does not mention whether it returns full tab details, IDs, or ordering; nor does it clarify that it is a read-only, non-destructive operation. This leaves ambiguity about the tool's behavior.

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 extremely concise—one sentence that conveys the core purpose. It is front-loaded and contains no unnecessary words. Every sentence earns its place.

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 is simple and has no output schema, the description is adequate but could be improved by mentioning what information the output contains (e.g., tab titles, URLs). Without this, the completeness is moderate.

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 input schema has 100% description coverage for its single parameter, so the schema already handles parameter meaning. The description adds no additional semantic value beyond what the schema provides, resulting in a baseline score of 3.

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 lists all open tabs ('すべての開いているタブを一覧表示する'), which is a specific verb+resource. However, it does not differentiate from sibling tools like arc_get_tabs_in_space or arc_search_tabs, which could cause confusion about when to use this tool over alternatives.

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 provides no guidance on when to use this tool versus other tab-listing tools. The parameter description in the schema offers minimal context about filtering by space, but the main description lacks any use-case or scenario suggestions.

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