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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds genuinely useful context beyond the annotations: the input must come from autocomplete and results are student property cards. It does not mention pagination behavior despite a page parameter, so it is not fully complete.

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, front-loaded with the action and scope, then the routing hint. Efficient with no filler, though "Results include matching student property cards" is slightly redundant against the stated purpose.

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 an output schema present, return values need not be explained, and the description covers purpose, input provenance, and alternatives. Combined with readOnly/openWorld annotations, an agent has enough to call it correctly; only pagination semantics are left implicit.

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%, so the baseline is 3. The description repeats the location-ID format example (REGION^87490) that the schema already documents and adds nothing about page, price, bedroom, or furnish filters, so it does not exceed the schema.

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 (search) and a precisely scoped resource (Rightmove student-accommodation listings), and explicitly contrasts itself with general sales or rentals, which maps cleanly onto the rightmove_search sibling. An agent can distinguish this from rightmove_search, rightmove_new_homes_search, and rightmove_commercial_search without opening any schema.

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?

"use this when looking for student housing rather than general sales or rentals" gives a clear when-to-use and an implicit when-not, and it points the agent at autocomplete as the source of the location ID. It does not name the alternative tool (e.g. rightmove_search) explicitly, so routing still takes one small inference.

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