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

Annotations are all false, so the description carries the full burden of behavioral disclosure. It clearly states that it needs no account equity or risk percentage, performs no position sizing, places no order, and changes the chart being built. It also instructs to call chart_link afterward, which is a required side-effect. No contradictions with annotations.

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 three sentences with no wasted words. It front-loads the purpose, then lists exclusions, names the alternative, and ends with the required follow-up action. Every sentence contributes directly to tool selection and correct invocation.

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 drawing tool with 9 parameters and no annotations, the description covers the core behavior, exclusions, and a required follow-up. It does not explain every parameter, but the optional ones are documented in the schema, and the main required fields are clear from context. The description is adequate for an agent to call the tool correctly without further research.

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 only 33% (only toTime, barsWide, and fromTime have descriptions). The description covers the core parameters entry, stop, and target implicitly, and side is implied by 'long/short,' but it does not explain symbol, timeframe, or the optional time/barsWide parameters. It adds meaning for the primary required fields but leaves the rest to schema or inference, which is insufficient given the low coverage.

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 ('Draw'), a clear resource (an entry, stop, and target box on a chart), and explicitly differentiates itself from position_plan_on_chart by noting it performs no quantity or risk calculations. This allows an agent to instantly distinguish it from the closest sibling tool.

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?

It explicitly names the alternative (position_plan_on_chart) and the condition that selects it: 'only when the user also wants quantity and risk calculations.' It also implies when to use this tool ('immediately when those price levels are known'), leaving no ambiguity about the appropriate context.

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