Lord of Prediction

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), lowering the bar. The description does add genuinely new behavioral context in pricing ("10 credits, Tier 1"), which helps an agent weigh cost, but says nothing about what the selection is based on or how it behaves with targetAge omitted/null.

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?

Front-loaded one-liner with structured metadata lines; zero filler. It is efficient, though the concision comes at the cost of substance rather than being tight prose.

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 explained, and the input schema is rich. But for a specialized Hellenistic technique with a domain term as its name, the description never explains what a "lord of prediction" is, what tradition-specific rule it applies, or when its result is appropriate — the core conceptual gap remains.

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 single body parameter is heavily documented (birth data, timezone/offset precedence, houseSystem letter codes), so the schema does the work. The description adds nothing about the meaning of targetAge or how it drives significator selection, so baseline 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?

"Predictive significator selection" essentially restates the tool title (a lord of prediction is a predictive significator) rather than explaining what the operation actually computes. There are dozens of Hellenistic/Schmidt siblings and none is named or contrasted, so an agent cannot tell this apart from e.g. hand_quarter_lord or levels_of_causation without outside knowledge.

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 guidance is given on when to invoke this versus the many other Hellenistic technique endpoints. The bracket metadata (group, endpoint, cost) is operational, not usage guidance; there are no prerequisites or exclusions stated.

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