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

Annotations already carry the full safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false), so the bar is lower. The description adds genuinely useful context beyond them: cookie values are masked (privacy behavior) and no key/credits/wallet are needed. The 'up to 50' limit duplicates the schema's maxItems, and no return behavior is described.

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?

Purpose is front-loaded in the first clause and the sentences are short and scannable. 'FREE during validation. No key, credits, wallet or preparation needed' is somewhat redundant padding, and 'Existing source and input limits apply' is vague 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?

An output schema exists, so return values need not be explained. For a single-input audit tool the description covers purpose, item limit, masking, and auth/pricing context; the only gap is the imprecise description of how to populate the nested 'input' parameter.

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 description coverage is 0%, so the description must carry the parameter burden. It links informally to the setCookies array via 'Check up to 50 Set-Cookie headers' (matching maxItems=50), but 'Supply your task in input' is vague and does not explain the required nested object shape or value format.

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 ('Check') plus resource ('Set-Cookie headers') and names the exact analysis ('security attributes and prefix rules') and that values are masked. It is clearly distinguishable from siblings like security_header_audit or security_csp_audit by its cookie-specific scope, though it never names a sibling outright.

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?

There is no when-to-use or when-not-to-use guidance and no alternative tool is referenced, despite several overlapping security siblings. The only conditional content ('FREE during validation') is pricing, not routing information.

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