wmts_add_layer

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

No annotations are provided, so the description bears the full burden. It describes the action (adding a layer) as a mutation but does not disclose side effects, permissions required, or behavior when a duplicate layer exists. It does partially address behavior for the tile_matrix_set parameter (default vs. specified). Given the lack of annotations, the description is moderately transparent but not comprehensive.

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 concise—only three sentences. The first sentence clearly states the purpose, and the following sentences add value by explaining key parameters. There is no redundant information, and every sentence serves a purpose.

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?

Given the tool has 7 parameters and an output schema (not described in description), the description covers the core functionality and key parameters. It does not discuss return values, but the presence of an output schema mitigates this. The description could mention behavior for duplicate layers or expected output format, but overall it is fairly complete for a straightforward tool.

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 input schema has 0% description coverage, so the description must compensate. It adds meaning for url, layer, and tile_matrix_set, which are critical, but does not describe crs, style, format, or layer_name. While the coverage is partial, the description adds significant value for the most important parameters, earning a score of 3.

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 'Add a WMTS raster (tiled) layer to the project,' specifying the verb 'add', resource 'WMTS raster layer', and context. It distinguishes from siblings like wms_add_layer by explicitly mentioning WMTS, making the purpose specific and 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 explains the key parameters (url, layer, tile_matrix_set) and references the auxiliary tool ows_list_capabilities for listing options. It provides guidance on optional parameters, such as omitting tile_matrix_set to let QGIS pick the default. While it doesn't explicitly state when not to use this tool, the context of sibling tools for other service types implies the appropriate use case.

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