prev_waybar_mode

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

Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=false, so the mutation-but-safe profile is covered. The description adds nothing about whether cycling wraps around at the first mode, how many modes exist, or whether the new mode is reported back — real behavioral gaps for a state-changing 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?

One short sentence, front-loaded with the action and target, with no filler or redundant restatement of the title.

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?

With no parameters, no output schema, and non-destructive read-write annotations, the definition is minimally sufficient. It still leaves open the wrap-around behavior at the end of the list and whether the resulting mode is surfaced to the caller, both of which matter for chained agent actions.

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 tool takes zero parameters, so there is nothing for the description to disambiguate beyond what the empty schema already shows; baseline 4 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?

Names a specific verb ('Cycle to the previous') and resource ('waybar layout mode'), which an agent can immediately distinguish from next_waybar_mode and set_waybar_mode. It does not explicitly name those siblings, but the directional wording makes the distinction obvious.

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 only implied: 'previous' signals directional stepping versus a direct set_waybar_mode call, but the description never states when to prefer one over the other or what happens at the boundary of the mode list.

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