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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), so the description focuses on content-level behavior: every block carries a source release, the optional address_id conditionally adds building and street sale aggregates, and the output is explicitly 'not advice and not a valuation'. It does not describe what happens when address_id falls outside area_id or whether the pack is expensive to build.

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?

A single front-loaded sentence introduces the pack before listing its blocks, with no filler. The enumeration is dense and takes effort to scan, and the 'as get_market_depth' phrasing is slightly awkward, but every clause carries substantive 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?

With an output schema present, the description need not explain return shapes, and it usefully pre-summarizes the blocks an agent will receive. The main gap is unspecified behavior for an address_id outside the given area and any latency or cost expectations for a multi-block pack.

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%, so the baseline is 3, but the description adds real meaning: address_id must be inside the area and its presence adds building and street sale aggregates, which is a conditional effect the schema only hints at. area_id's geography semantics remain schema-driven.

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?

Names a specific resource (an area evidence pack) and enumerates its constituent blocks: market depth, crime rate, noise shares, state schools with Ofsted grades, and address-level sale aggregates. The parenthetical 'as get_market_depth' explicitly ties one block to a sibling tool, letting an agent distinguish this composite from the single-metric siblings.

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?

Usage is only implied: the enumerated blocks suggest this is a bundled alternative to calling get_market_depth, get_home_prices, get_flood_risk and peers separately, and the address_id clause hints at when to pass it. There is no explicit 'use this when…' routing or exclusion against siblings such as get_area_overview.

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