Primary Directions

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the description adds only the method names and output type. It does not disclose prerequisites or side effects beyond what annotations cover, but adds moderate context.

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 description is concise with two core sentences plus a metadata block and example. It avoids fluff, but the metadata could be integrated better. The example is helpful for understanding typical input.

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?

Given 11 parameters, no output schema, and decent annotations, the description is incomplete. It lacks parameter explanations, usage guidance, and output details, leaving significant gaps for an agent to proceed confidently.

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 0% for 11 parameters. The description only provides an example request body without explaining any parameter purpose, format, or constraints. This fails to compensate for the missing schema descriptions.

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 description clearly states it calculates primary directions (Ptolemaic or Regiomontanus) up to a maximum age and returns a timeline of directed aspect hits. This distinguishes it from other prognostics tools like symbolic_directions and firdaria among siblings.

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 explicit guidance on when to use this tool versus alternatives. The description includes a group label and cost but no when-to-use or when-not-to-use conditions, leaving the agent without selection criteria.

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