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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds only that the response is the listing's full text with a citable URL; it says nothing about failure modes for a bad id or content limits.

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. It is tight, though arguably too terse given the naming collision with get_listing that a clause could have resolved.

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?

An output schema exists, so return values need not be explained, and the tool is simple (one required param). What is missing is any statement of how this differs from get_listing/search_listings, which the agent needs to route correctly among five siblings.

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 0% and the lone id parameter is documented only as a bounded string. The description partially compensates by telling the agent the id comes from a search result, which is real semantic value, but it omits any id format or example.

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 a specific verb (fetch) and resource (full text of one listing) plus a scope qualifier ('by id from search'), so the operation is clear. However, it never distinguishes itself from the sibling get_listing, whose name suggests the same resource, leaving overlap the agent must resolve on its own.

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?

'by id from search' implies the id originates from a search call, which is a useful usage cue, but there is no explicit when-to-use statement, no exclusion, and no routing between fetch, get_listing, or search_listings. Usage is only implied.

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