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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior. The description adds genuinely useful context beyond that — the 10-credit cost tier and the Brennan-tradition grouping — but discloses nothing about the returned period structure or how the 80-year default horizon affects output.

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?

Three short, front-loaded lines with no filler; the technique and interpretive domain come first. Slightly under-specified rather than verbose, but nothing wastes space.

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?

With an output schema, complete annotation coverage, and fully-described parameters, the structured fields carry most of the burden. The remaining gap is routing guidance among the many close Hellenistic ZR siblings, which the description does not address.

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%; the nested birth-data object, `fields`, and `precision` are all thoroughly documented in the schema itself. The description adds no parameter semantics, so the baseline of 3 applies.

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 a specific technique verb+resource: 'Zodiacal Releasing from Lot of Fortune' with the interpretive domain ('body/livelihood periods'). This distinguishes it reasonably from the sibling ZR-from-Spirit tools, though the distinction is implicit in 'Fortune' rather than stated. The alias note clarifies its relationship to the canonical tool name.

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 is given. It does not tell the agent when to pick this over `..._zodiacal_releasing_spirit`, `..._zr_loosing_of_bond`, or `..._zr_peak_periods`, nor what question the Lot of Fortune periods answer versus the Spirit lot. The alias line explains naming, not usage.

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