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

Annotations already declare the full safety profile (readOnly, idempotent, non-destructive, closed-world). The description adds genuinely new operational context: the POST endpoint, the 5-credit / Tier ½ cost, and the required date. It does not describe what the response contains or any limits, but with annotations covering behavior, this is a reasonable addition.

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 definition is short and front-loads the topical keywords before the structured metadata block. Every line is compact, though the keyword fragment is terse to the point of under-specification rather than wasteful.

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?

An output schema exists, so return values need not be described, and the metadata block covers endpoint, required input, and cost. Still missing is what the tool actually produces conceptually and how it relates to the rest of the Zi Wei suite, leaving it only minimally adequate for a 6-parameter chart tool.

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 a middling 67%, and the one parameter lacking a schema description ('date') is merely restated in the description as '[Required: date]' — which duplicates the schema's required array rather than explaining format or semantics. For timezone/precision/fields the description adds nothing beyond the schema's own text.

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 title 'Property Palace (Tianzhai)' plus the keyword fragment 'Real estate, family home, ancestry' identifies the topical domain and differentiates it from the other Zi Wei palace siblings (career, spouse, wealth, etc.). However, it never states a verb or deliverable — an agent must infer that the tool computes/returns a Property Palace reading from a birth date. Specific but not a verb+resource statement.

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 when-to-use guidance, no mention of alternatives (e.g., astroway_ziwei_twelve_palaces or astroway_ziwei_full_chart), and no indication of what input conditions are appropriate. The bracketed metadata lists required fields and cost but does not help the agent decide between this and a sibling.

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