Penta Chart

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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so safety is covered. The description adds genuinely useful operational context the annotations do not: the POST /v1/hd/penta endpoint and the 100-credit (Tier 4) cost, which matters for call planning.

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?

One tight sentence front-loads the purpose and output shape, followed by a compact tagged metadata block. No filler or repetition of schema content.

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 present and annotations covering the safety profile, the description only needs purpose, inputs cardinality and cost — all of which it supplies. The remaining gap is sibling differentiation against astroway_hd_group_overlay, which an agent selecting among ~500 tools would want.

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?

There is a single 'inputs' array parameter, and the description only notes it must carry 3–5 people, matching minItems/maxItems. The nested item schema carries rich prose on date/time formats, timezone behavior, ayanamsa and houseSystem, so the schema does the heavy lifting; the description adds little beyond the cardinality constraint.

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 ('Calculate') and resource ('Penta (group) chart'), plus scope (3–5 people) and what the result is ('combined BodyGraph showing group dynamics and collective conditioning'). It is clear on its own, but never distinguishes itself from close siblings such as astroway_hd_group_overlay or astroway_relational_group_synastry.

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 '3–5 people' phrase implies the usage context, and the metadata line '[Required: inputs]' signals the prerequisite. There is no explicit when-to-use/when-not guidance and no pointer to the sibling tools that also produce group charts, leaving the agent to infer the choice.

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