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

Annotations already declare readOnly/idempotent/non-destructive/openWorld=false, so the safety profile is covered. The description adds genuinely non-structured context: cost (10 credits, Tier 1), the endpoint, and the scope limit of 7 classical planets. It does not discuss caching or per-call limits, but against the annotation baseline this is solid added value.

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?

Very short and front-loaded: the purpose sentence leads, followed by scannable bracketed metadata. Nothing is padded, though the bracket block is terse enough to be cryptic rather than efficient.

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 15-parameter tool with 33% schema coverage, the definition leaves key mechanics unexplained — notably how a moment/location chart maps to a sign ruler and whether the sidereal enums affect the result. An output schema exists so return values need not be described, but the interpretive link between inputs and the herb list is missing.

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%, so the description needs to compensate and does not. Its 'Required: date, time, latitude, longitude' line merely restates what the schema already enforces, and it says nothing about city, name, cosmogram, zodiacType, houseSystem, or how ayanamsa/zodiacType choices change which planetary ruler is used.

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?

Names the resource (herbs) and the organizing principle (traditional planetary ruler per Culpeper, all 7 classical planets), which does differentiate it from the other wellness siblings like crystals or diet. However, it never states what the response contains or which sign's ruler is being used, even though the tool requires a full chart (date/time/lat/long). The purpose is inferable but not pinned down.

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?

No when-to-use guidance and no routing to or from the nine sibling wellness tools (biorhythm, crystals, diet, exercise, etc.). The only selection help is the bracketed cost and required-parameter line, which is metadata rather than usage context.

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