set_active_layer

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

No annotations are provided, so the description carries the full burden. It only says 'Set the active layer,' which implies a state change, but does not disclose side effects, error behavior if the layer does not exist, or any impact on subsequent operations. This is a significant gap for a mutation tool.

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 a single sentence, but it essentially restates the tool name and provides no extra information. It is under-specified rather than appropriately concise, similar to the 'Process' example where brevity comes at the cost of usefulness.

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 no annotations, no output schema, and only a minimal description, the tool lacks essential context such as prerequisites, behavior, and return value. For a simple setter, it might be acceptable, but the absence of any additional information makes it incomplete for an agent to use confidently.

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 100% coverage for the single parameter 'layerName' with description 'Layer name to activate'. The tool description adds no additional semantics beyond the schema, so the baseline of 3 applies.

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 'Set the active layer' clearly states the action (setting) and the resource (active layer). It distinguishes from sibling tools like create_layer and list_layers, though it doesn't explicitly clarify what 'active layer' means or its significance.

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?

There is no guidance on when to use this tool versus alternatives, no prerequisites (e.g., layer must exist), and no mention of typical use cases. The agent is left without context for selecting this tool appropriately.

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