Read cookies

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

Annotations already declare readOnlyHint=true, so safety of the operation is covered; the description adds genuinely new context by naming the BiDi storage.getCookies call, noting values are returned as stored, and warning they should be treated as secrets. It stops short of describing result size or pagination 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?

Three short sentences, front-loaded with the action, then scoping, then the security caveat. Nothing is wasted and each 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?

For a zero-required-parameter read tool with full schema coverage and annotations, this is nearly complete: it explains what is listed, how to narrow, and how to handle the returned values. The only omission is any hint about result volume or handling of large cookie sets.

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?

Schema coverage is 100%, so both parameters are already documented in the schema; the description's 'filter by name and/or domain' adds meaningful framing (they compose as optional narrowing filters) but no syntax or matching rules beyond that. Baseline 3 applies.

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 cookies visible to the browser') and grounds it in the underlying BiDi call. The 'List' verb distinguishes it from siblings like browser_set_cookie and browser_delete_cookies, though it never names them explicitly.

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 covers scoping ('Filter by name and/or domain to narrow it down') but gives no guidance on when to reach for this tool versus alternatives such as browser_import_cookies or browser_search_prefs, and no prerequisites or constraints are mentioned.

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