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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, covering the safety profile. The description adds critical behavioral context: 'Only publicly visible locations are returned; private residences are excluded.' This goes beyond annotations and informs the agent about data filtering. It also mentions 'suspicious-detection counts' as part of the output, providing extra utility. No contradiction exists.

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 three concise sentences: purpose, use case, and privacy note. It is front-loaded with the core action, then provides a practical usage scenario, and ends with a key behavioral constraint. Every sentence earns its place with no wasted words.

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?

For a 6-parameter tool with no output schema, the description covers the main semantics, a practical use case, and an important filtering rule. It hints at the return content ('suspicious-detection counts') but does not describe result ordering or pagination. Given the rich annotations and partially described schema, this is reasonably complete for an agent to invoke correctly. It could be a 5 if it mentioned response list characteristics, but a 4 is fair.

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 descriptions cover days, radius_meters, and response_format (50% coverage). The description itself does not elaborate on parameters, particularly 'limit', which lacks a schema description. It does implicitly reference latitude/longitude by saying 'near a latitude/longitude', but adds no technical detail. Given moderate schema coverage, the description neither compensates nor detracts, so a baseline 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 function: 'Find locations near a latitude/longitude that SkimGuard users have scanned recently, with suspicious-detection counts.' It uses a specific verb (find) with a resource (locations) and details the scope (near coordinates). The phrase 'Use for "any skimmers reported near me?"' further clarifies its purpose and distinguishes it from sibling tools like search_locations or my_locations.

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 an explicit use case: 'Use for "any skimmers reported near me?".' This tells the agent when the tool is appropriate. However, it does not mention alternatives or when not to use it, but the context is sufficient for selection among the sibling tools. This warrants a 4 rather than a 5.

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