set_navigation_layers

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

With no annotations provided, the description carries the full burden for behavioral disclosure. It adds the 'exactly one' constraint and implies the bitmask is replaced wholesale, but it does not state behavior when the node path is invalid, when more than one input is provided, or whether the operation is reversible. These gaps are notable for a mutating 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, well-structured sentence that front-loads the verb and object, specifies input formats, and adds the 'exactly one' constraint without any wasted words. Every component contributes to understanding.

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's simplicity and lack of output schema, the description covers the primary use and main constraints. However, it omits error handling, prerequisites for the target node, and the effect on existing layer settings. For a mutation tool with no annotations, these are important contextual gaps, but the description is adequate for a basic understanding.

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 description maps the parameters layers, layer_bits, and layer_names to raw mask, 1-based bit numbers, and project layer names, and clarifies their mutual exclusivity. This compensates for the complete lack of schema descriptions. However, node_path is not explicitly described, though its meaning is inferable from the 'navigation region or agent' phrase.

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's action: setting the navigation_layers bitmask on a navigation region or agent. It also lists the three accepted input formats (raw mask, 1-based bit numbers, project layer names), allowing easy distinction from sibling tools like setup_navigation_region or setup_navigation_agent.

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 instructs to 'give exactly one' of the three layer specification methods, which is a critical usage rule for this tool. It implies the context of modifying an existing navigation region/agent, but does not name alternative tools or explicitly state when this tool is preferred over setup_navigation_region or setup_navigation_agent.

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