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

With no annotations the description must carry the behavioral load, and it does disclose several traits: zero credit cost, 'explicit and bounded' source acquisition, and that estimates retain dates/scope/confidence. It does not disclose pagination (cursor) behavior, permission/auth needs, or that the operation is read-only.

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?

It is reasonably front-loaded and dense, but the middle sentences ('Source acquisition is explicit and bounded', 'Ad text and Publisher ID reverse lookups cover the recorded collection') are jargon-heavy and add little actionable clarity for the space they consume.

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?

This is a high-complexity tool (11 params, two enums, required tool+q, no output schema, no annotations), and the description covers only the tool/data-source dimension. Pagination via cursor, the region enum, and the DR/visit/age range filters go entirely unexplained, leaving an agent under-equipped to invoke it correctly.

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 0% across 11 params, so the description must compensate. It does map the cryptic `tool` enum values to semantics (google-ads by domain/advertiser, meta-ads by keyword, adsense by publisher, outbound-links by page, ad-keywords, dr-growth/discovery), which is real added value, but the numeric filters (minDr/maxDr, minVisits/maxVisits, maxAgeMonths, limit, region, cursor) remain entirely undocumented.

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 names the resource (standalone site research) and enumerates the concrete data sources it queries — Google ads, Meta ads, AdSense, outbound links, DR changes — so an agent knows what the tool produces. It is clearly differentiated from lookup-style siblings by the 'standalone research' framing, though it never names a sibling directly.

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 repeated 'free / 0 credits / early-access' framing gives implied routing guidance (use this when you don't want to spend credits), and 'standalone' hints at it not requiring a workspace. But there is no explicit when-to-use-vs-alternatives statement against lookup_domain, compare_bulk, or get_research_workspace.

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