Layer Selection Count

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds a genuine behavioral detail beyond those annotations: it will not fall back to the total row count, informing the agent that the result reflects only the actual selection. It doesn't cover edge cases like zero-selection behavior explicitly, so not a 5.

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 front-loaded sentence with no filler; the key behavioral caveat is stated compactly and every clause earns its place.

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?

An output schema exists, so return values need not be explained, and annotations cover the safety profile. The description supplies the crucial behavioral nuance about not falling back to total rows. It is largely complete, with only per-parameter detail left to the schema (which unfortunately documents nothing).

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 0%, so the schema provides no per-parameter documentation and the description adds none either. However the three required parameters (aprx_path, map_name, layer_name) have self-evident names that make their meaning clear, keeping this at a minimum-viable 3 rather than lower.

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 states a specific verb+resource: reads the exact count of selected features for a given layer. The clause '不回退为总行数' further scopes it (returns selection count, not total row count), which meaningfully distinguishes it from a generic count. It does not explicitly name the sibling tools (e.g. arcgis_pro_layer_selection_fids, arcgis_pro_table_selection_count), keeping it just below 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?

Usage is implied from the name and description (get the selected feature count for a layer), but there is no explicit guidance on when to use this versus arcgis_pro_layer_selection_fids or the table/current-layer selection siblings. No exclusions or prerequisites are stated.

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