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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is clear. The description adds valuable behavioral context by stating 'Updates: on source cadence' and clarifying the days parameter behavior (history requires Gold tier, else current snapshot). This goes beyond the annotations without overcomplicating.

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 two sentences plus an 'Updates' note, front-loading the core purpose and output fields. Every sentence contributes value: the first defines the deliverable, the second gives usage triggers, and the note adds freshness context. There is no waste or repetition.

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?

The tool is simple with one optional parameter and no required inputs. The description lists all output fields in the response, provides usage triggers, and notes the update cadence. Given the annotations and schema cover safety and parameter details, the description is complete for effective selection and invocation.

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 schema description coverage is 100% because the only parameter (days) has a detailed description in the input schema. The tool description itself does not add parameter meaning beyond the schema, but the schema already explains the optional nature and Gold tier requirement. This is a baseline 3 situation where the schema carries the parameter documentation load.

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 specifies a clear verb ('Returns'), a specific resource (soil and land quality score for 3,222 US counties), and enumerates the exact output fields (score, national_percentile, ranked drivers, methodology_version, confidence). It clearly distinguishes itself from the many sibling tools by focusing on this specific index.

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 explicit when-to-use guidance: 'Call when the user asks about local soil or farmland quality, land productivity, or growing conditions, or when timing farmland acquisition, lease pricing, project siting, or agricultural lending decisions.' This gives the agent a rich set of triggers and decision contexts, effectively covering the intended use cases.

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