browser_get_cookies

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

With no annotations provided, the description carries the burden of behavioral disclosure. It reveals the constraint that the site must be open in a tab, which is valuable, but doesn't disclose the return format (e.g., JSON structure) or potential errors beyond refusal. This is adequate but not rich.

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 long with no fluff. The core action and constraint are front-loaded, and the prerequisite is placed second. Every word contributes to understanding.

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 single-parameter read operation with no output schema, the description covers the essential context: what it does, the prerequisite, and the limitation. Minor gaps like error handling or return format are not critical given the low complexity.

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 schema description for the 'domain' parameter is already detailed, including the example and the note that it must match an open tab. The description reiterates the domain scope but adds little new semantic meaning beyond the schema, so a baseline 3 is appropriate given 100% coverage.

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 specifies the verb 'get' and the resource 'cookies for a site', and clearly indicates the domain scope (site itself, parent domain, or subdomain). However, it doesn't explicitly contrast with the sibling browser_set_cookies, which could cause slight ambiguity, though the action is distinct enough.

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 explicitly instructs to navigate to the site first and warns that cookies for non-open sites are refused. This provides clear conditions for use and implies when it should not be used, effectively guiding the agent on prerequisites.

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