compare_areas

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

Annotations already declare readOnlyHint=true and destructiveHint=false, indicating a safe read operation. The description adds context about comparing 'side by side on the Praesago Trajectory Index', but does not disclose any additional behavioral traits such as whether the comparison is based on a specific metric, how results are presented, or any limitations. With annotations covering safety, the description adds minimal extra transparency.

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 a single concise sentence that front-loads the key action ('Compare two UK postcode districts'). It contains no filler or redundant information, making it efficient for an agent to parse.

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?

Despite having no output schema, the description fails to explain what the comparison returns (e.g., a score, a table, a chart). It only mentions 'side by side on the Praesago Trajectory Index', which is vague. For a tool with two parameters and no output schema, the description should provide more context on the result format to help the agent understand what to expect.

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?

The input schema has 100% description coverage: both 'area_a' and 'area_b' include descriptions with examples (e.g., 'E17', 'N15'). The description does not add any further meaning beyond what the schema provides, so a baseline score of 3 is appropriate.

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 clearly states the tool's purpose: comparing two UK postcode districts side by side on the Praesago Trajectory Index. It uses a specific verb ('Compare') and resource ('UK postcode districts'), and it distinguishes itself from sibling tools like 'get_area_score' (single district) and 'search_areas' (search, not compare).

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?

The description provides no guidance on when to use this tool versus alternatives. It does not specify when to use 'compare_areas' over 'get_area_score' or 'get_area_context', nor does it mention any prerequisites or exclusions. The usage is implied but not explicitly clarified.

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