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

Annotations already indicate a safe read operation (readOnlyHint, destructiveHint=false, idempotentHint). The description adds behavioral value by stating it returns attribute rows and geometry, and it offers the sampling idiom. The default limit and max limit are in schema, so description doesn't need to repeat. This is solid coverage beyond 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?

Three sentences: purpose, parameter list, and usage tip. Every sentence earns its place with no fluff. Front-loaded with the primary action.

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 effectively communicates return shape (attribute rows and geometry). It also gives sample usage patterns and parameter formatting. For a moderate-complexity tool with good schema coverage, this is 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?

Schema covers 100% of parameters, so baseline is 3. The description adds slight semantic value by noting the URL comes from search_datasets and clarifies the SQL-like nature of where and comma-separated out_fields, though these are already in schema. The extra hint about sourcing the URL nudges it to a 4.

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 queries an ArcGIS Feature/Map Service layer by URL, with a specific verb (Query) and resource (layer). It distinguishes from siblings like layer_info (metadata) and search_datasets (finding datasets), and even references search_datasets as the URL source.

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?

It provides clear context on when to use the tool (after obtaining URL from search_datasets) and gives a practical sampling tip (where='1=1' + out_fields='*'). However, it does not explicitly mention alternatives or when not to use it, so it stops short of a 5.

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