Listingrail property listings

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

Annotations already establish readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds real value beyond them by disclosing cost ('Free') and by enumerating the semantic content of the response (country, rent/sale, accepted filters, location syntax) despite there being no output schema. It stops short of saying whether the listing is static or reflects live account state.

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?

A single tight sentence with zero filler; the return-content list is front-loaded and the cost note is placed last. The fragmentary grammar ('The portals search_listings can read: …') is slightly harder to parse than a clean verb-first sentence.

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?

For a zero-parameter, read-only listing tool with an output schema absent, the description carries the needed burden by enumerating the fields each portal entry exposes. An agent has enough to decide to call it and to use the result. Only the relationship/protocol with search_listings remains implicit.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. Nothing in the text suggests hidden argument surface, which is the right signal for a no-arg call.

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 names the resource (the portals that search_listings can read) and enumerates the per-portal information returned, so an agent knows exactly what this call yields. It differentiates from the only sibling by framing itself as metadata *about* the portals search_listings queries. It reads as a noun phrase rather than a verb+resource statement, which keeps it just short of a 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?

Naming search_listings implies this is a discovery step to run before searching, but the description never says so explicitly and gives no when-not-to-use condition or alternative. An agent can infer the sequencing, but it must infer it.

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

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

The description successfully adds critical behavioral context that is not in the annotations, such as the complete list of 20 portal names, the data points returned (price, photos, etc.), and the cost of failure (costs nothing). This adds significant operational transparency beyond the simple read-only hint.

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 very dense and long, but this is justified because every sentence conveys highly specific, non-redundant information necessary for the agent to interact with the complex, multi-source API correctly. It sacrifices brevity for density.

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 integrating 20 different external APIs, the description is extremely complete. It covers data scope, required external knowledge (via list_sources), and economic behavior (credits), leaving no vital operational gaps.

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?

Although schema coverage is 100%, the description provides invaluable semantic context by listing all valid portal keys and grouping them by country. This helps the agent understand the structural requirements of the 'source' and 'location' parameters far beyond a simple enum list.

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 is maximally clear, defining the tool's function as searching live sale and rental listings across 20 specific property portals. It lists the types of data aggregated into the single response schema.

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?

It provides essential usage guidance by referencing the sibling tool 'list_sources' to instruct the AI agent on which location formats and portal-specific filters must be used. It also clearly outlines the cost structure (1 credit/listing).

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