Lollipop Chart

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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior. The description adds that the tool renders a chart (non-destructive) and supports optional target markers, but goes beyond what annotations provide. It does not elaborate on other behavioral aspects like resource usage or side effects.

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 highly efficient sentences: first defines purpose and visual, second adds features and usage context. No filler, each sentence earns its place.

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 6 parameters, 100% schema coverage, and annotations, the description covers purpose, key features, and usage context. It lacks details on parameters like theme or effects, but those are self-explanatory from the schema. The description is sufficiently complete for a straightforward chart tool.

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?

Schema coverage is 100%, achieving baseline 3. The description adds value by explaining that the tool 'supports optional target markers for benchmarking,' which directly informs the target parameter. However, it does not elaborate on the other parameters (theme, effects, etc.), but they are adequately described in the schema.

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?

Description clearly states the tool renders a lollipop chart for comparing segments, with horizontal lines and dots. Also mentions optional target markers and positions it as a cleaner alternative to bar charts, effectively distinguishing it from sibling chart tools like render_bar_chart.

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 specifies the tool is for 'How do segments compare?' and labels it a 'Clean alternative to bar charts for ranked data,' giving clear context for when to use it over bar charts. However, it doesn't explicitly state when not to use it or mention other alternatives like dumbbell charts.

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