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

The description frames the operation as a pure data retrieval ('will provide you with the number of backlinks'), which is read-only semantics, yet the annotations declare readOnlyHint=false, idempotentHint=false, and destructiveHint=true. This directly contradicts what the description implies, so per the rubric this is an annotation_contradiction. The description also fails to disclose permissions, rate limits, or the cost of batching up to 1000 targets.

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 sentences, front-loaded with the core purpose and followed by the definition of 'live' backlinks. It is reasonably tight, though slightly wordy in the parenthetical enumeration of attributes.

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-value explanation is not required, and the parameter details live in the schema. The remaining gap is the absence of sibling-selection guidance, but for a well-scoped data-fetch endpoint the description is otherwise complete enough to call 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?

The description references the targets array and clarifies that results cover domains, subdomains and pages, matching the schema. However, the schema itself already carries detailed parameter documentation (targets formatting rules, the 1000-target limit, tag purpose), so the description adds little beyond what the structured field provides.

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 a specific verb+resource: it returns the number of backlinks pointing to domains, subdomains, and pages in the targets array. It is clear and concrete, but it does not explicitly differentiate itself from closely related siblings like post_dataforseo_backlinks_referring_domains_live or the other bulk_* backlink endpoints; the only separation is the word 'number'.

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 states what the endpoint returns but gives no when-to-use guidance, no conditions for choosing it over the many sibling backlink endpoints (anchors, referring_domains, bulk_ranks, etc.), and no prerequisites or exclusions. The agent is left to infer selection purely from the tool name.

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