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

Goes well beyond the annotations: discloses the pricing model ($0.10 USDC per call, x402 or prepaid), that it is excluded from the free trial, the data pedigree (official open data, OGL), a privacy/privacy-scope caveat (statistics only, no addresses of private homes), and recency (crime stats latest month). The annotations' readOnly/openWorld/idempotent=false profile is consistent with the description.

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 core purpose and then a dense but justified enumeration of the five data categories, followed by the pricing/eligibility line. Given the composite scope, every clause maps to a distinct capability an agent needs to judge fit.

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 values, yet it still scopes contents, recency, data licensing, privacy limits, and cost. For a paid, one-parameter composite report, nothing material 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% and the single 'postcode' parameter is already documented as a full UK postcode with the England-and-Wales caveat for house prices. The description adds no syntax, format, or validation detail beyond the schema, so the baseline 3 applies.

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+resource ('UK area report for a postcode') and enumerates exactly what the report contains: local authority/ward/constituency, street crime by category, house-price stats, food-hygiene ratings, AI summary. An agent can tell this is the aggregated bundle tool rather than the raw siblings (uk-postcode, uk-house-prices, uk-food-hygiene).

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?

'in one call' communicates the aggregation benefit versus calling the individual UK data tools, and it flags 'Paid only (not in the free trial)' plus the $0.10 price, which is genuine selection context. It lacks an explicit 'use X instead if you only need Y' routing statement against siblings like uk-area or uk-postcode.

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