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

No annotations are provided, so the description carries the full burden and does so well: it discloses no-account/public-data access, decodes the return statuses ('behind_login', 'unavailable', 'no_permanent_tier'), and explains subdomain normalization. This is exactly the behavioral context the agent needs and cannot get from structured fields.

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?

Front-loaded with purpose, then behavior, then exclusions in a logical order, with every sentence carrying information. Slightly dense across three long sentences and could be tightened, but nothing is wasted.

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 output schema and only one fully-documented parameter, the description supplies everything an agent needs: purpose, cost semantics, status meanings, normalization, auth posture, and exclusions. Nothing essential is missing.

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 the baseline is 3, but the description adds semantics beyond the schema: 'A subdomain is priced as its registered domain, returned as pricing_domain', clarifying normalization behavior the schema only hints at. Modest but genuine added value.

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+resource: reports whether Zyte API supports a website and its pay-as-you-go cost, with the exact unit (USD per 1000 requests) and fields (httpResponseBody, browserHtml). It differentiates from siblings by naming zyte_api_usage_stats as the tool for spend data.

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?

Explicitly carves out what this tool is NOT for: plan prices, limits, discounts, and past spend, routing the latter to zyte_api_usage_stats. The condition 'public data, no account needed' also tells the agent this requires no auth, which is actionable usage guidance.

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