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

Annotations already declare the operation as read-only, idempotent, and non-destructive. The description adds concrete behavioral context by specifying the response contents: fields (name + type), geometry type, total record count, and capabilities. This goes beyond the annotations and tells the agent what to expect from the call, filling the gap left by the absence of an output schema.

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, front-loaded sentence that immediately states the action and resource, then lists the key outputs. Every word earns its place; there is no fluff 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?

For a tool with one parameter, rich annotations, and no output schema, the description is adequately complete. It enumerates the return values, compensating for the lack of a structured output schema. It does not address potential error conditions or variations between Feature and Map Service layers, but these are secondary for such a focused metadata operation.

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 covers the sole parameter `url` with a clear description and an example, achieving 100% schema coverage. The description adds no additional parameter-level detail beyond the schema, so the 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 uses a specific verb ('Get') connected to a clear resource ('ArcGIS Feature/Map Service layer's schema') and enumerates the exact outputs (fields with types, geometry type, record count, capabilities). This clearly differentiates it from sibling tools like query_layer, which likely retrieves data rather than metadata.

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 implicitly defines when to use the tool: when you need schema/metadata for a layer. It does not explicitly mention alternatives or exclusions, but the purpose is clear enough to guide selection. No misleading statements; clear context without explicit when-not-to-use guidance.

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