Zillow56 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 the tool lists similar properties but doesn't describe key behaviors: whether it's a read-only operation, what the output format looks like (e.g., list structure, pagination), any rate limits, or error conditions. For a tool with zero annotation coverage, this is a significant gap in transparency.

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 a single, efficient sentence that directly states the tool's purpose and input options without unnecessary words. It's front-loaded with the core function ('List of similar for rent properties'), making it easy to parse. However, it could be slightly more structured (e.g., separating purpose from input guidance) for optimal clarity.

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 search/list operation with 3 parameters), lack of annotations, and no output schema, the description is incomplete. It doesn't cover behavioral aspects (e.g., read-only nature, output format), usage guidelines, or how to handle the optional parameters. For a tool in this context, more detail is needed to adequately guide an AI 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?

Schema description coverage is 100%, meaning the input schema already documents all three parameters (zpid, url, address) with descriptions. The description adds minimal value by listing the input options ('by Zpid or URL or address') but doesn't provide additional semantics beyond what's in the schema (e.g., format details, examples beyond the schema's url example, or how parameters interact). This meets the baseline of 3 when schema coverage is high.

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: 'List of similar for rent properties' with specific input options (by Zpid, URL, or address). It uses a specific verb ('List') and resource ('similar for rent properties'), making the function unambiguous. However, it doesn't explicitly differentiate from sibling tools like 'similar_properties_similar_for_sale_properties' or 'similar_sold_properties_similar_sold_properties', which would be needed for a score of 5.

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 no guidance on when to use this tool versus alternatives. It doesn't mention any prerequisites, exclusions, or compare it to sibling tools (e.g., 'similar_properties_similar_for_sale_properties' for sale properties). Usage is implied through the input parameters but not explicitly stated, leaving gaps for an AI agent to infer context.

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