layer_set_crs

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

With no annotations provided, the description carries full burden. It clearly states the tool only relabels CRS metadata and does not reproject coordinates—a critical behavioral trait. However, it could add more about side effects (e.g., modifying layer metadata) or prerequisites (e.g., layer must exist).

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 plus a brief note about a planned alternative. It is front-loaded with the primary action, uses no unnecessary words, and is highly 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?

The tool is relatively simple, and the description covers the essential function and key distinction (no reprojection). It doesn't mention return values, but an output schema exists. For a metadata-setting operation, this is mostly complete, though it could note that the layer is modified.

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 provides an example for the crs parameter ('EPSG:2180'), but does not explain the format explicitly or describe layer_id. For a two-parameter tool, this is adequate but leaves some ambiguity.

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 action ('Assign a layer's CRS metadata') with an example format ('EPSG:2180'). It explicitly distinguishes from reprojection, differentiating it from sibling tools like crs_transform_point and the planned layer_reproject.

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 explicitly says when to use ('fix a layer that was loaded with a missing or wrong CRS') and when not to use ('does not reproject coordinates'). It even mentions a planned alternative (layer_reproject), though it could reference existing sibling tools for coordinate transformation.

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