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

Annotations already declare the tool as read-only, idempotent, and non-destructive, so the safety profile is covered. The description adds value by specifying the returned data (fields, geometry type, record count, capabilities), which goes beyond the annotations and clarifies what the agent can expect from the call.

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, focused sentence that front-loads the primary action and then lists the specific output details. Every word contributes meaning, with no filler or redundant information.

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 simple one-parameter tool with strong annotations and no output schema, the description sufficiently explains what the tool does and what information it returns. It covers the key aspects of the tool's behavior and output, making it complete in this context.

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 has 100% coverage with a clear description for the single 'url' parameter including an example. The tool description's mention of 'by url' adds nothing beyond the schema. Since the schema already does the heavy lifting, a baseline score of 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 a specific verb ('Get') and resource ('ArcGIS Feature/Map Service layer's schema'), and enumerates the exact output contents: fields, geometry type, total record count, and capabilities. This distinguishes it from sibling tools like 'query_layer' and 'search_within' which imply data retrieval rather than schema inspection.

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 implies the tool is for retrieving schema information but does not explicitly mention when to use it instead of alternatives, nor any exclusions or prerequisites. There is no direct comparison with sibling tools, leaving the agent to infer usage from the tool name and description.

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