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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds the rendering convention (BPHS, fixed North Indian layout) and the 10-credit cost, which is useful operational context but does not disclose return format, SVG-vs-JSON default behavior, or other 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 prose is two front-loaded sentences followed by compact metadata tags. It is appropriately sized for a rendering tool and contains no filler or repetition.

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 schema, annotations, and output schema carry most of the burden, and the description identifies the chart style. However, in a catalog with multiple Vedic wheel variants, the absence of selection guidance leaves a meaningful gap for an agent choosing among siblings.

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%, and the three top-level parameters are already richly documented in the schema. The description adds no parameter syntax, defaults, or constraints beyond what the schema provides, so the baseline of 3 is appropriate.

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 names the specific chart layout (North Indian diamond chart) and its structural rule (12 fixed positions, signs rotate per ascendant), plus the BPHS standard. That is enough to distinguish it from at least the South Indian and Western wheel siblings, but it stops short of explicitly naming those alternatives or stating the rendering action as a verb.

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?

There is no guidance on when to choose this wheel over astroway_render_wheel_vedic_east, astroway_render_wheel_vedic_south, or astroway_render_wheel_western. The group and cost labels give operational context but do not tell the agent when this tool is the right selection.

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