Ahrefs MCP Server

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

No annotations are provided, so the description carries full burden. It mentions 'extensive filtering, sorting, selection, and aggregation options' and a 'timeout' parameter, hinting at complexity and potential performance considerations. However, it lacks critical behavioral details such as rate limits, authentication requirements, data freshness, pagination behavior, or what happens on errors—significant gaps for a tool with 10 parameters and no output schema.

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?

The description is two sentences: the first states the purpose and scope, the second provides a procedural note. It's relatively concise but could be more front-loaded with critical usage context. The second sentence, while helpful, feels like a workaround for missing schema documentation rather than integral guidance.

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?

Given the tool's complexity (10 parameters, 0% schema coverage, no annotations, no output schema), the description is insufficient. It outlines the high-level purpose but misses essential details: parameter meanings, behavioral constraints, output format, and differentiation from siblings. The note to use 'doc' tool acknowledges the gap but doesn't make this description complete on its own.

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 compensate. It vaguely references 'filtering, sorting, selection, and aggregation options' and mentions a 'timeout' parameter, but fails to explain the purpose, syntax, or allowed values for any of the 10 parameters (e.g., 'target', 'select', 'where', 'aggregation'). The directive to use the 'doc' tool shifts responsibility but doesn't add semantic value within this description itself.

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 clearly states the tool retrieves detailed information about all backlinks for a specified URL or domain, with specific filtering/sorting/aggregation options. It uses the verb 'retrieves' with the resource 'backlinks,' but doesn't explicitly differentiate from sibling tools like 'site-explorer-backlinks-stats' or 'site-explorer-broken-backlinks' beyond mentioning 'all backlinks.'

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 includes a directive to 'Use doc tool first to get the real input schema,' which provides some procedural guidance. However, it offers no explicit guidance on when to use this tool versus alternative backlink-related tools (e.g., for stats vs. detailed lists), nor does it mention prerequisites or exclusions beyond the schema note.

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