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

The description goes well beyond the annotations by adding concrete behavioral facts: cost per size, free repeat calls for known-empty queries, the quote-first workflow for size 100, and the return fields (backlinks, referring domains, pages, first seen). These are exactly the side-effect and workflow details an agent needs and that are not available from annotations or parameter names.

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 succinct sentences cover metrics, cost tiers, empty-query behavior, and the confirmation workflow. No filler or redundancy; the most important operational caveats are front-loaded.

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 read-only look-up tool, the description supplies essential response semantics (top `limit` anchors, aggregate fields), cost behavior, and the non-obvious quote confirmation step. Combined with the rich schema, an agent has enough to call and interpret the result without external docs. No output schema exists, so these textual details are especially valuable.

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 already fully documents all four parameters, so the baseline is 3. The description adds value by explaining cost implications of size, the quote/confirm_quote_id flow for size 1000, and free retries on empty results. This goes beyond the schema without duplicating it.

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 definition identifies exactly what the tool returns: anchor texts for a target, with per-anchor metrics (backlinks, referring domains, pages). Though phrased as a noun, the intent is unambiguous and matches the name backlinks_anchors, and it differentiates well from sibling tools like backlinks_pages or backlinks_competitors.

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 tells what the tool does but gives no guidance about when to choose it over alternatives such as backlinks_pages or domain compare tools. There is no explicit 'use this when...' or 'instead of...' direction. The cost/quote rules are workflow details, not selection guidance.

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