List sidebars and their state

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

readOnlyHint=true already declares the safe-read profile, so the bar is lower; the description still adds substance by declaring the return fields and the fact that it is exhaustive across all sidebar types. It does not mention ordering of results or whether sidebars unavailable in the current window are omitted, which is the only remaining behavioral gap.

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?

One main clause carries the resource, the returned fields, and the exhaustive scope, followed by a single short sentence on the id's downstream use. Front-loaded, no filler.

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?

With no parameters and no output schema, the description supplies the return shape (id, title, open state) that would otherwise be undocumented, which is exactly what is needed to call it confidently. Minor omission: nothing about result ordering or behavior when no sidebar is open.

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?

Zero-parameter tool, so the baseline is 4 by rule. The description correctly implies no input is needed and instead spends its words on the output contract, which is the right allocation.

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?

Specific verb (list) + resource (sidebars) with an inline enumeration of the sidebar categories and an explicit statement of what is returned (id, title, currently-open one). It is unmistakably distinct from browser_set_sidebar, which is the mutation counterpart.

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?

"Use the id with browser_set_sidebar" establishes the discover-then-mutate workflow and points at the correct alternative tool. It stops short of stating when not to call it (e.g., if the id is already known, listing is unnecessary), so it is clear context rather than full when/when-not guidance.

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