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

Annotations already declare destructiveHint=true and idempotentHint=true, but the description never explains what is destroyed: per the schema, the full listing list overwrites prior saved listings. It does add one piece of context not present in annotations or any output schema, namely that the call yields a URL the agent must share, which is genuinely useful.

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 front-loaded sentence with no filler. The trailing clause about sharing is slightly awkwardly attached but still earns its place as the only statement of what to do with the result.

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 valuably discloses that the return is a shareable custom URL. However, for a destructive, non-idempotent-looking write with a required contactId prerequisite, it omits the overwrite consequence and the sequencing dependency, leaving those to the schema.

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%, including a strong warning about never guessing contactId, so the baseline is 3. The description adds no parameter-level meaning and does not reinforce the overwrite semantics of listingIds, leaving the schema to carry it entirely.

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 verb+resource ("Save listings") is clear, but the stated destination, "a custom URL," conflicts with the schema's "save to the user's profile, overwriting any previous saved listings." The description never distinguishes this from siblings such as listing_details or search_properties, so an agent must infer when this write path is the right one.

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?

There is no explicit when-to-use, when-not-to-use, or alternative-tool guidance. The only guidance is the vague instruction that the result "should then be shared by the agent," which describes a post-step rather than a selection criterion. The prerequisite (a contactId from send_contact_info) is documented only in the schema, not the description.

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