HD Design Date

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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds genuinely useful operational context not in the annotations: the endpoint (POST /v1/hd/design-date) and the cost (10 credits, Tier 1). It says nothing about auth requirements, rate limits, or whether the result is cached, which keeps it at a 3.

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 core sentence is front-loaded and wastes no words, and the bracketed metadata lines are compact. Some of that block (Required:) duplicates structured schema data rather than earning its place.

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?

This is a 13-parameter computational tool with low schema coverage; the description never addresses the many optional astrological configuration parameters or the important timezone-vs-timezoneOffset interaction. Output schema exists, so return values need no explanation, but for a tool of this complexity the description is under-specified.

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 23% across 13 parameters, so the description must compensate — but it only repeats the four required field names already listed in the schema's 'required' array. The nine optional parameters (city, name, cosmogram, zodiacType, houseSystem, ayanamsaId, and the timezone vs timezoneOffset precedence) are left unexplained by the description.

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?

States a specific verb and resource ('Find the Design date ... for a given birth moment') and defines the concept precisely as 88° of solar arc before birth, plus the interpretive meaning ('unconscious imprinting point'). An agent can distinguish it from the broader HD chart siblings without opening the schema.

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?

Only prerequisite-style information is given ('Required: date, time, latitude, longitude'). There is no guidance on when to use this versus astroway_hd_human_design or astroway_hd_hologenetic, and no exclusions or alternative routes are named.

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