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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, covering the safety profile. The description adds a concrete contract of returned data (schema, geometry, count, capabilities), including the potentially expensive 'total record count' operation, which is useful beyond annotation defaults. No contradictions with 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?

A single, well-structured sentence with no filler. The verb 'Get' and resource 'layer's schema' are front-loaded, and the list of returned items is compact and efficient.

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 read-only tool with one param and no output schema, the description sufficiently explains what the tool returns and the target resource type. The absence of an output schema is compensated by the explicit list of return elements, making the tool's behavior predictable.

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 provides 100% coverage for the single 'url' parameter with description and example. The description only references 'by url' without adding extra semantics, so it meets the baseline but does not elevate 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's function: 'Get an ArcGIS Feature/Map Service layer's schema by url' and enumerates exact return items (fields, geometry type, record count, capabilities). This distinguishes it from data-querying siblings like query_layer, making the purpose unambiguous.

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 for retrieving layer schema/metadata but does not explicitly mention when to use this tool versus alternatives (e.g., query_layer for features). No when-not-to-use guidance is provided, so the agent must infer context.

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