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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful behavior beyond them: places are scored independently and a failing place is reported in its own row while others still return, which tells the agent that partial failure is expected and not an error condition.

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?

Three sentences, front-loaded with what it does and what comes back, then partial-failure semantics, then the coverage exclusion. No filler, no repetition of the schema's enum values, and every sentence carries information the agent needs.

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?

There is no output schema, and the description compensates by naming the returned columns (overall score, area type, strongest dimension, one-line summary) and their ordering. Combined with the coverage limit and partial-failure rule, nothing an agent needs to invoke and interpret this tool 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 preset enum already enumerates moving/business/investing/research with detailed explanations, so the schema is doing the heavy lifting. The description only adds that one preset is applied uniformly across all places ('the same decision preset'), which is a modest clarification rather than new meaning.

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 gives a specific verb+resource pair ('Scores 2 to 8 places ... for the same decision preset') plus the output shape, so an agent immediately knows this is a multi-place comparison rather than a single lookup. It never names a sibling (e.g. score_postcode for one place, find_areas for discovery), so differentiation is implied by cardinality rather than stated.

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?

Explicit negative guidance is given: 'There is no data for places outside England, Wales and Scotland, such as Belfast; do not call it for them.' That is a real when-not rule with a concrete example. It stops short of naming the alternative to use for a single place or for out-of-coverage locations.

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