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

readOnlyHint=true already covers the safety profile, and the description adds workflow behavior: results are 'candidates' needing human confirmation, and downstream tools must not run on an unconfirmed guess. It stops short of describing ambiguous or empty-result behavior, so not a full 5.

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 sentences, zero filler, with the entry-point rule front-loaded ahead of the caution. Every clause carries an instruction the agent needs.

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 entry-point search with no output schema, the description covers the essential behavior. It omits what happens on multiple or zero matches, which would help an agent interpret results, but nothing critical to correct invocation is missing.

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 coverage is 100% and the schema already gives a concrete example ('14 Acacia Road, CV4 7AL'). The description only restates 'address or postcode' without adding format or matching semantics, so baseline 3 is appropriate.

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 and resource ('Find candidate properties') plus the input modality ('by address or postcode'). It clearly reads as the discovery/entry-point tool, distinct from the get_* siblings that appear to operate on an already-identified property.

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?

Gives explicit sequencing ('Always call this first'), a user-confirmation step before invoking other tools, and a negative instruction ('never guess which property was meant'). This is exactly the when/when-not guidance the dimension asks for.

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