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

Annotations already cover read-only, open-world, idempotent, and non-destructive behavior. The description adds valuable transparency by specifying the output contents (fields, geometry type, total record count, capabilities), which goes beyond the annotation hints. It doesn't mention error handling or URL validity, but for a simple read tool this is adequate.

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 sentence that front-loads the purpose and lists the key outputs without any filler. Every word contributes meaning, making it highly concise and well-structured.

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 one-parameter, read-only tool with full schema coverage and rich annotations, the description is complete. It enumerates the exact return values (fields, geometry type, count, capabilities), which is sufficient since no output schema exists. The tool's simplicity means no additional context is necessary.

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 schema description fully covers the 'url' parameter with a type, example, and explanation. The description's mention of 'by url' adds no new semantics beyond the schema. Since schema_description_coverage is 100%, the baseline of 3 is appropriate; the description doesn't need to compensate.

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') and identifies the resource ('an ArcGIS Feature/Map Service layer's schema'), clearly stating what the tool does. It enumerates the exact information returned (fields, geometry type, record count, capabilities), which distinguishes it from siblings like query_layer that would fetch data.

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 usage when needing layer schema information, but it does not explicitly state when to use this tool versus alternatives like query_layer or search_within. No exclusions or alternative tool recommendations are provided, leaving the agent to infer the appropriate context.

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