generate_line_chart

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

Annotations provide readOnlyHint=true, indicating this is a safe read operation. The description adds context by specifying the chart type (line chart) and its purpose (showing trends over time), which is useful beyond annotations. However, it doesn't disclose behavioral traits like output format (e.g., image URL, base64), error handling, or performance considerations. With annotations covering safety, the description adds some value but lacks rich behavioral details.

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 concise and front-loaded, stating the purpose in the first sentence. The example adds clarity without being verbose. However, it could be slightly more structured by explicitly mentioning key parameters or usage scenarios, but overall, it's efficient with minimal waste.

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 complexity (8 parameters, nested objects) and lack of output schema, the description is moderately complete. It covers the core purpose and provides an example, but doesn't explain the output (e.g., what is returned, such as an image or chart object), which is a gap since there's no output schema. With good schema coverage and annotations, it's adequate but could better address missing elements like result format.

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 description coverage is 100%, so the schema fully documents all 8 parameters. The description doesn't add any parameter-specific semantics beyond what's in the schema; it only gives a high-level example without explaining individual parameters. Since the schema does the heavy lifting, the baseline score of 3 is appropriate, as the description doesn't compensate but also doesn't detract.

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: 'Generate a line chart to show trends over time.' It provides a specific verb ('Generate') and resource ('line chart'), with an example illustrating its use for time-series data. However, it doesn't explicitly differentiate from sibling tools like 'generate_area_chart' or 'generate_scatter_chart', which might also show trends over time, leaving some ambiguity about when to choose a line chart specifically.

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 minimal guidance on usage. It includes an example ('such as, the ratio of Apple computer sales to Apple's profits changed from 2000 to 2016'), which implies use for time-based trends, but lacks explicit when-to-use criteria, prerequisites, or alternatives. No mention is made of when to choose this over sibling tools like 'generate_area_chart' or 'generate_bar_chart', leaving the agent to infer based on the example alone.

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