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

Annotations already establish that this is a safe, idempotent read, and the description adds substantial behavioral context: returned neighbour fields, the combined block contents, tolerance-based adjacency, ring widening, UK scope, credit cost, and the important distinction that an unowned neighbour means no linked registered title rather than no owner. Nothing conflicts with the annotations.

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?

The description is front-loaded with the core purpose, then moves cleanly through return content, addressing, adjacency semantics, caveats, and cost/workflow. Despite being relatively long, every sentence contributes useful operational context.

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?

The tool is complex with eight parameters and no schema descriptions, but the description covers the main identifiers, adjacency controls, output shape, scope, cost, and key semantic caveat. It is nearly complete, with the notable remaining gap being same_owner_only and, to a lesser extent, limit.

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%, so the description must carry parameter meaning, and it does explain the four subject identifiers plus tolerance_m and ring_m. However, it leaves limit and same_owner_only unexplained, and same_owner_only is behaviorally important enough that this is only a partial compensation for the schema gap.

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 states a specific verb/resource: adjacent parcels and their owners, with the combined-site output explicitly named. It distinguishes this from a simple parcel lookup by emphasizing adjacency analysis and aggregate owner/constraint results, so an agent can tell what this tool is for without opening the 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?

It clearly frames the tool as the first step in a site assembly, explains how to address the subject parcel, and gives the address workflow via address_autocomplete and address_resolve. It also notes UK-only availability and credit cost, though it does not explicitly state when to choose sibling tools such as parcel_lookup or area_report instead.

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