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. It states the tool is for searching, implying a read-only operation, but doesn't disclose behavioral traits such as pagination handling (implied by the 'page' parameter), rate limits, authentication needs, or what the search returns (e.g., list of agents with basic info). This leaves gaps in understanding how the tool behaves beyond its basic function.

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, clear sentence with no wasted words. It's front-loaded with the core purpose and efficiently states the key parameters, making it easy to parse quickly.

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 complexity of a search tool with 5 parameters, no annotations, and no output schema, the description is incomplete. It doesn't explain the return format (e.g., what data about agents is included), how pagination works with the 'page' parameter, or how multiple criteria interact. This leaves significant gaps for an agent to use the tool effectively.

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%, with all parameters documented in the schema (e.g., 'location' as required, 'page' with default '0'). The description adds minimal value by mentioning 'location and name' as search criteria, which aligns with the schema but doesn't provide additional semantics like format hints or usage examples beyond what's already in the schema descriptions.

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: 'Search for agents by location and name'. It specifies the verb ('Search') and resource ('agents'), and mentions two search criteria. However, it doesn't differentiate from sibling tools like 'agents_active_listings' or 'agents_past_sales' which might also involve agent data, though those seem to serve different purposes (listing vs. searching).

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 sibling tools like 'agent_details_by_username' for specific agent details or 'search_for_properties_by_neighborhood_city_or_zip' for property searches, leaving the agent to infer usage based on context alone.

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