Ahrefs MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions the tool allows 'comparison between current and previous data,' hinting at a read-only comparison function, but fails to detail critical behaviors such as data retrieval limits, error handling, authentication needs, rate limits, or output format. This leaves 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 the second provides a usage instruction. It is front-loaded with the core function, but the second sentence is somewhat tangential (directing to another tool for schema details) rather than enhancing the tool's own usage context, making it less efficient than ideal.

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, no annotations, no output schema), the description is insufficient. It outlines the basic purpose but lacks details on behavioral traits, parameter meanings, output structure, and differentiation from siblings. Without annotations or output schema, the description should provide more comprehensive guidance to enable effective tool use, which it does not.

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%, meaning none of the 10 parameters are documented in the schema. The description only vaguely references 'specified project and date' and 'comparison between current and previous data,' which loosely maps to 'project_id,' 'date,' and 'date_compared' parameters. It does not explain the purpose, format, or constraints of other parameters like 'device,' 'limit,' 'order_by,' 'select,' 'timeout,' 'volume_mode,' or 'where,' failing to compensate for the lack of schema documentation.

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's purpose: 'Provides an overview of competitor rankings and keyword metrics for a specified project and date in Ahrefs Rank Tracker, allowing comparison between current and previous data.' It specifies the verb ('provides an overview'), resource ('competitor rankings and keyword metrics'), and context ('Ahrefs Rank Tracker'), but does not explicitly differentiate from sibling tools like 'rank-tracker-overview' or 'management-project-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 includes a usage instruction: 'Use doc tool first to get the real input schema,' which provides a prerequisite step. However, it offers no guidance on when to use this tool versus alternatives (e.g., other rank-tracker or competitor-related tools), nor does it specify exclusions or contextual triggers for its use.

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