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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower, and the description adds real value beyond them: it specifies the data scope ('everything public') and calls out a notable exclusion ('Seller contact is not included'), which is exactly the kind of gap an agent would otherwise guess at.

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?

Two compact sentences, zero filler, and the return payload is front-loaded ahead of the caveat. Every clause carries information.

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?

With no output schema, the description carries the burden of describing return content, and it does so by enumerating fields and flagging what is absent (seller contact). For a single-id read tool this is complete enough to call correctly.

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?

One parameter at 100% schema coverage, and the schema already explains that the id comes from search_listings. The description adds no syntax, format, or validity information beyond the schema, so the baseline 3 applies.

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?

States a specific verb+resource ('Get a listing') and then enumerates the returned payload (title, description, photos, price, size, rooms, place, similar homes), which lets an agent distinguish it from summary-style siblings like search_listings. It stops short of explicitly naming which sibling to use for which need, so it is clear but not sibling-differentiating.

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?

Usage is only implied: the exclusion of seller contact hints that reveal_seller is the tool for that data, and the schema (not the description) points to search_listings as the id source. There is no explicit when-to-use statement or named alternative routing.

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