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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true, so the safety profile is covered. The description adds that it 'Returns attribute rows (and geometry)' and gives a sampling tip, but does not disclose pagination behavior, response limits, or any potential external side effects. This is acceptable but not rich beyond 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 two sentences, front-loaded with the core purpose, and includes a practical quick-start tip. Every sentence earns its place with no redundancy or fluff.

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?

With no output schema, the description appropriately explains the return type ('attribute rows (and geometry)'). It also provides enough context for typical usage, including the source of the URL, key parameters, and a sampling strategy. The tool's complexity is well-covered by the combination of description and schema.

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?

Schema description coverage is 100%, so the baseline is 3. The description briefly restates parameter names and adds 'SQL-like' and 'comma-separated' semantics, but these are already implied in the schema descriptions. The sampling tip is a useful addition but does not significantly deepen parameter understanding beyond the schema.

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: 'Query an ArcGIS Feature Service / Map Service layer by its url'. It uses a specific verb (query) and resource (Feature/Map Service layer), and distinguishes itself from sibling tools like search_datasets and layer_info by focusing on data retrieval from a known layer URL.

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 provides clear usage context by indicating the URL comes 'from search_datasets', establishing a workflow prerequisite. It also offers a sampling tip ('Use where="1=1" + out_fields="*" to sample'). However, it does not explicitly mention alternatives or when not to use this tool, though the context is sufficiently clear.

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