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

The description explains that the operation changes the chart being built and that chart_link must be called afterward, which goes beyond the annotations. It also clarifies that the indicator is hidden/shown rather than destroyed, aligning with destructiveHint=false and readOnlyHint=false.

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 two sentences long, front-loads the core purpose, and every sentence earns its place. It is clear, direct, and free of unnecessary detail.

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?

The tool is simple with one parameter and no output schema, and the description covers purpose, usage context, and mutation behavior. However, the missing explanation of instanceId is a notable gap that prevents the description from being fully self-sufficient.

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 does not explain what instanceId refers to; schema coverage is 0%. While the tool name suggests it identifies an indicator, the definition leaves the parameter meaning implicit and does not compensate for the schema's lack of description.

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 states a specific verb ('hide or show') and resource ('an indicator'), and differentiates itself from removal with 'without removing it.' It clearly communicates the tool's purpose and distinguishes it from sibling tools like chart_remove_indicator.

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 gives clear context: it is useful for comparing a chart with and without an indicator, and it instructs the agent to call chart_link when done. It does not explicitly spell out when not to use it, but the 'without removing it' phrasing implies the boundary with removal tools.

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