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

Annotations already declare readOnlyHint=false, idempotentHint=true, destructiveHint=false and a closed-world scope, so the safety profile is covered. The description usefully adds that results are reported per cookie and that the operation is scoped to a single domain, but it does not disclose whether unknown cookies are created, how partial failures are surfaced, or what permissions are required.

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?

Two tight sentences, with the core action and scope front-loaded and the value source following. The enumerated category list partially duplicates the schema enum and could be shortened to the package reference, but overall there is little wasted text.

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?

An output schema exists, so return shape needs no explanation, and the annotations cover idempotency and non-destructiveness for a write operation. What remains thin is the create-versus-update semantics for cookies not already known to the account, which matters for a mutating batch tool.

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 50% and domainId already carries its own description, so the schema does the heavy lifting. The description's main addition is naming @cookiepal-oss/cookie-db as the authoritative source for category values, but the enumerated list it repeats is already present in the schema enum, and the batch size limit and per-item required fields are left to the schema.

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 gives a specific verb and resource ('Sets the category for a list of cookies') plus scope ('on one of your CookiePal domains') and a batch-report side effect. No sibling tool in the list performs classification, so the agent can place it unambiguously, though the description never explicitly says what it is not.

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?

Usage is only implied: it is for assigning categories to a batch of cookies, and the category must come from the @cookiepal-oss/cookie-db package. There is no statement of when to prefer this over any other tool, no prerequisites (domain access, existing scan data), and no guidance on whether cookies must already be known to CookiePal.

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