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

No annotations are supplied, so the description carries the full behavioral burden. It does disclose scope (UK-only postcodes) and freshness qualifiers ('recent crime', 'live flood warnings'), which is real signal. It says nothing about aggregation latency, rate limits, cost, partial-failure behavior when one upstream source misses, or coverage gaps across UK constituent countries.

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 resource and its full contents, then the use cases. Every clause carries information; nothing is redundant or padded.

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?

An output schema exists, so return-value structure need not be explained, and the description instead covers contents and audience. For a multi-source aggregate with zero annotation coverage, the remaining shortfall is operational behavior: latency, partial results, and when a narrower sibling would be cheaper.

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?

There is a single parameter with 100% schema description coverage ('UK postcode.'), so the schema already does the work. The description reinforces the UK-only scope but adds no format or normalization guidance (e.g., spacing, casing, partial postcodes). Baseline 3 is appropriate when the schema is fully documented.

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 names the resource (a UK postcode due-diligence report) and enumerates every data section returned: admin areas, recent crime, live flood warnings, food hygiene, and Land Registry prices. That enumeration makes clear it is the composite/aggregate tool relative to the narrower siblings. It stops short of an explicit verb phrase or a stated relationship to the single-purpose siblings, so it is clear but not maximally differentiating.

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 contexts are given concretely: property searches, relocation, site selection, lead enrichment. That tells an agent when this tool is a good fit. However, there are no exclusions or routing hints — nothing says to prefer crime_summary, flood_warnings, or house_prices when only one dimension is needed, which matters for a heavier aggregate call.

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