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 pagination semantics ('page paginates') and a hint that location must be resolved via autocomplete, but discloses nothing about result caps, rate limits, or empty-result behavior. With annotations plus an output schema, the remaining behavioral burden is low, so a 3 is appropriate.

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 dense sentences with zero filler, front-loaded with the core purpose and field list before the routing guidance. Every clause carries information.

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 two-parameter read-only list tool with an output schema and full annotation coverage, the description supplies everything needed: purpose, scope, field inventory, pagination, and sibling routing. Nothing an agent needs to call it correctly 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 description coverage is 100%, so both parameters (location, page) are already documented in the schema. The description reinforces that location is the driver and page paginates, but adds no syntax, format, or range detail beyond what the schema provides. Baseline 3 is correct when the schema does the heavy lifting.

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 ('List') plus the exact resource ('Rightmove estate-agent branch records') and enumerates the returned fields (name, brand, address, phone, sales/lettings flags, logo, branch link). It also explicitly distinguishes itself from rightmove_agent_branch (one branch) and rightmove_search (property listings), so an agent can route 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?

Names three alternatives with the condition that selects each: rightmove_autocomplete to resolve a location, rightmove_agent_branch for a single branch, rightmove_search for property listings. This is explicit when-to-use and when-to-use-something-else guidance, leaving nothing to inference.

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