list_fields

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

No annotations are provided, so the description carries the burden; 'List' implies a read-only operation but that is never stated, nor is there any note on permissions or pagination behavior for layers with many fields. It does disclose the returned field attributes, which is some behavioral value, but the safety profile is left to inference.

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?

A single front-loaded sentence with zero filler that names the resource and the exact payload returned. Nothing could be trimmed without losing meaning.

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?

An output schema exists, so return shape needn't be explained, and all three parameters are fully documented in the schema. The only gap is the absent when-to-use guidance, which matters little for a simple read-only listing tool.

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% (map_name, wildcard, layer_name all documented inline including the wildcard example and the get_layers cross-reference), so the baseline is 3. The description adds nothing about the map or wildcard filtering options.

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?

States a specific verb and resource ('List a layer's fields') plus the returned attributes (type, alias, length, domain), which separates it from siblings like get_layer_info or get_field_statistics. It stops short of naming an alternative tool or explicit scope limits, so it is clear but not fully differentiated.

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?

There is no statement of when to use this versus get_layer_info, get_field_statistics, or describe_dataset, and no prerequisites or exclusions. Usage is only implied by the name and by the schema's reference to get_layers.

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