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

Beyond the readOnly/idempotent annotations, the description discloses that results are raw assets joined to HIFLD/EIA, that substations include count and max voltage_kv, that transmission is a >69 kV path overlay, and that power plants include operating and planned status. This gives an agent an accurate behavioral model without contradicting the annotations.

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 front-loaded with the resource and layer list, then gives return details, an example, and an explicit exclusion. Each sentence earns its place; the only minor redundancy is 'nearby infrastructure' vs 'raw nearby assets', which does not hurt clarity.

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 read-only lookup tool with an output schema and fully documented parameters, the description is complete: it covers what is returned, the data source, the supported questions, an example call, and when not to use the tool. Nothing an agent needs to select and invoke it correctly 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%, so the schema already documents all nine parameters. The description adds a usage example and notes radius_km is configurable, but it does not add significant meaning beyond the schema's own per-parameter descriptions.

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 identifies a specific resource — nearby infrastructure around a lat/lon point — and enumerates the exact layers returned: substations, transmission lines, pipelines, and power plants. It also distinguishes itself from analyze_site by explicitly saying it returns raw assets rather than a scored verdict.

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?

It states the intended use cases with example questions ('what is near this parcel', 'how far is the nearest substation and what voltage') and gives a concrete invocation example. It explicitly warns against using it for a single scored site-suitability verdict and names analyze_site as the correct alternative.

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