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

Annotations already declare the tool as readOnly, idempotent, and non-destructive, so the bar is lower. The description adds value by specifying the return content (schema, fields, geometry, count, capabilities) but does not mention error handling, URL validation, or other behavioral details. It does not contradict 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 a single, front-loaded sentence that conveys the tool's function and output list with no wasted words. It is efficiently structured and immediately actionable.

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 read-only tool with one well-documented parameter and no output schema, the description covers the essential details: what the tool does and what it returns. It could mention that it is safe/read-only, but the annotations already cover that, making the description sufficiently 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 provides 100% coverage for the single 'url' parameter, explaining it is a Feature/Map Service layer URL with an example. The description merely says 'by url' without adding additional syntax or format details, so it meets the baseline but does not exceed it.

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 the tool gets an ArcGIS Feature/Map Service layer's schema and enumerates the specific data returned (fields, geometry type, record count, capabilities). This is a specific verb+resource combination, though it does not explicitly differentiate from sibling tools like query_layer, so it falls short of a 5.

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?

No guidance is provided on when to use this tool versus alternatives such as query_layer or search_within. The description implies usage when needing schema information, but it lacks explicit context, exclusions, or alternative tool references.

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