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

Annotations already declare readOnlyHint and idempotentHint, so safety is covered. The description adds value by specifying the precise schema components returned (fields, geometry, count, capabilities), which sets concrete expectations beyond the generic annotation hints.

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, well-structured sentence that front-loads the purpose and uses a concise list for outputs. Every part earns its place, and there is no redundancy or filler.

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?

With one well-documented parameter and no output schema, the description compensates by clearly listing all expected return elements. Given the tool's simplicity and the read-only annotations, this is fully complete.

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 description for `url` is complete and includes an example, giving 100% coverage. The tool description only repeats the notion of 'by url' without adding new parameter nuances, so it carries no additional semantic weight.

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 uses a specific action ('Get') and a clear resource ('ArcGIS Feature/Map Service layer's schema'), enumerating exactly what is returned (fields, geometry type, record count, capabilities). This distinguishes it from sibling tools like query_layer, which would focus on data retrieval rather than metadata/schema.

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 clearly implies this tool is for retrieving schema metadata, giving the agent context on when to use it. However, it explicitly mentions no alternatives or exclusionary criteria, so it stops short of full usage guidance.

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