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

Annotations already declare readOnlyHint, idempotentHint, closed-world and non-destructive behavior, so the safety profile is covered. The description adds two genuinely useful facts beyond annotations — the credit cost (10, Tier 1) and the required parameter set. It does not disclose how timezone/ayanamsa defaults affect results, which matters for a chart tool.

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?

Compact and front-loaded: the meaning sentence comes first, followed by terse bracketed metadata. No meandering prose. The bracket fields are dense but each carries operational value, so little is wasted.

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, return values need not be explained, and annotations cover the safety profile; required inputs and cost are given. However, for a 15-parameter chart tool the absence of any guidance on zodiac/house/ayanamsa options leaves the definition only minimally adequate.

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 33%, so the description must compensate, but it only restates the four required parameters already marked required in the schema. It says nothing about behavior-affecting optional params (zodiacType, houseSystem, ayanamsa, timezone vs timezoneOffset) that materially change the output, leaving those enums unexplained in both places.

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 names a specific astrological resource ('Classical planetary joys') and anchors it with a concrete example ('Sun-Leo-9th'), so an agent can tell what domain it computes. The '[Group: Hellenistic: Brennan tradition]' tag distinguishes it from the many other Hellenistic sibling tools. It lacks an explicit verb (e.g. 'returns/computes'), keeping it just short of a 5.

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?

There is no statement of when to use this tool versus alternatives, no prerequisite context (it needs a full birth moment), and no routing to related tools such as lots_15 or bonifications_maltreatments. The only usage signal is the machine-readable bracket metadata listing required params and cost.

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