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

Annotations already declare readOnlyHint=true, so the safety profile is covered; the description adds value by enumerating what the response contains (date, state, agents, property, price expectations, commission estimate) in the absence of an output schema. It also discloses the underlying endpoint, though it says nothing about behavior when the id does not exist.

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 short sentences, front-loaded with the operation and scope, followed by the id source. Every clause carries information; nothing is repeated from the title or schema.

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 single-parameter read tool with no output schema, the description covers purpose, input provenance, and a useful sketch of returned fields. Only missing pieces are failure behavior (unknown id) and any auth or rate considerations, which are minor here.

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 schema documents the single id parameter at 100% coverage, so the baseline is 3. The description earns an extra point by explaining where the id originates (search or autocomplete), which is provenance information the schema does not provide.

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 ('One appraisal by id') and immediately differentiates scope from the plural search tool by emphasizing a single record. It also previews the returned fields, so an agent knows exactly what it gets. It stops short of naming rex_search_appraisals outright, relying on 'a search' to imply it.

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 id comes from a search or autocomplete' tells the agent the precondition for calling this tool and implicitly routes it to rex_search_appraisals / autocomplete when no id is held. There is no explicit when-not guidance or error/not-found behavior, but the usage context is unambiguous.

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