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 states 'Retrieves,' implying a read-only operation, but doesn't disclose other traits like authentication needs, rate limits, error handling, or what the return format looks like (e.g., list of keywords, JSON structure). For a tool with zero annotation coverage, this leaves significant gaps in understanding how it behaves beyond the basic action.

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 extremely concise and front-loaded: the first sentence states the core purpose, and the second provides critical usage guidance. Every sentence earns its place with no wasted words, making it easy for an agent to parse quickly and efficiently.

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 (a read operation with one parameter), lack of annotations, no output schema, and 0% schema description coverage, the description is incomplete. It covers purpose and usage prerequisites but misses behavioral details (e.g., return format, errors) and parameter semantics. For a tool in this context, more information is needed to fully guide the agent.

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 input schema has 0% description coverage (no parameter descriptions), and the description doesn't add any semantic meaning for the 'project_id' parameter beyond implying it's required. It doesn't explain what a project ID is, how to obtain it, its format, or valid ranges. With low schema coverage, the description fails to compensate, leaving the parameter poorly understood.

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 verb ('Retrieves') and resource ('keywords associated with a specific project in Ahrefs' Rank Tracker'), making the purpose specific and understandable. It distinguishes itself from siblings like 'management-projects' (which likely lists projects) by focusing on keywords for a specific project. However, it doesn't explicitly differentiate from keyword-related siblings (e.g., 'keywords-explorer-matching-terms'), slightly limiting clarity.

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 provides explicit guidance on when to use this tool: 'Use doc tool first to get the real input schema.' This directly addresses prerequisites and workflow, helping the agent understand the required sequence of actions. It doesn't mention alternatives, but the clear prerequisite instruction is sufficient for a top score in this context.

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