setup

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

Annotations declare readOnlyHint=true and destructiveHint=false. The description adds context that this is a walkthrough that presents choices and tells how to set the profile, not actually mutate state. It implies interactivity ('ASK the user') but doesn't specify behavior if the profile is already set, which is a minor gap.

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?

Two sentences, front-loaded with the core function, followed by usage context. Every word earns its place, no redundancy or fluff.

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?

For a 0-parameter informational tool with no output schema, the description covers purpose, timing, and content. It mentions the profile choices and the ask-action. The only missing piece is an explicit statement that it doesn't modify state, but annotations cover that.

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 has 0 parameters and schema coverage is 100%. No parameter explanation is needed; baseline 4 applies. The description adds no param info, but none is required.

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 purpose: to show cost-profile choices (saver/balanced/max) and guide the user through configuring spending. The specific verb 'show' and the resource 'cost-profile choice' distinguish it from sibling tools like usage_report or reset_lane_state.

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 provides explicit when-to-use guidance: 'Call this on first use if the profile isn't set'. It also instructs to 'ASK the user', which clarifies the interactive workflow. It doesn't mention when not to use, but the conditional is clear.

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