Penta Chart

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

Annotations already indicate readOnlyHint, destructiveHint, idempotentHint, and openWorldHint, so the description's behavioral burden is low. It adds cost information (100 credits) but no additional behavioral traits, which is adequate given the annotations.

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 two sentences plus a clear example, efficiently conveying the tool's purpose and showing usage. It is well-structured and front-loaded with the action, though it could be slightly more detailed without losing conciseness.

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?

The description states the output is a combined BodyGraph showing group dynamics, which is helpful. However, without an output schema, agents cannot know the exact structure of results. The cost and example add context, but deeper explanation of the Penta concept is missing.

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?

The schema has 0% description coverage, so the description must compensate. It provides an example request body showing required fields (date, time) and optional defaults, but many parameters (e.g., houseSystem, zodiacType, cosmogram) are unexplained, leaving agents unclear about their meaning or necessity.

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 the tool calculates a Penta (group) chart for 3-5 people, producing a combined BodyGraph for group dynamics. It is specific and differentiates from generic chart tools, though it does not explicitly contrast with sibling group tools like hd_group_overlay.

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?

The description provides an example and cost but no guidance on when to use this tool versus alternatives such as group_synastry or hd_group_overlay. The only usage constraint is the group size (3-5 people), leaving the agent to infer the rest.

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