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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and a closed world, so the safety profile is covered. The description usefully discloses the report contents (pillar pairs plus resulting element) and the credit cost (Tier 1, 10 credits), which annotations do not carry. It says nothing about determinism against the input, error behaviour, or how a chart with no interactions is represented.

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?

A single dense sentence front-loads the most distinctive content (the interaction types) before the secondary details. Nothing is redundant, though the enumeration is long and the appended group/cost tags are bracketed boilerplate rather than prose.

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?

An output schema exists, so the description need not spell out return values, and it covers the computed content well. However, for an 11-parameter chart tool with patchy schema documentation, the absence of any statement about required birth data, the stageSchool choice between classical and unified, or the includeFullTable toggle leaves the agent under-informed about how to call it.

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?

With 11 parameters and only 36% schema description coverage, the description should carry meaning for the undocumented inputs, but it mentions none of them — not date, time, timezone, trueSolarTime, stageSchool, includeFullTable, fields, precision or language. The schema leaves several of these bare, so the gap is real rather than theoretical.

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 concrete resource — the set of stem/branch interactions (combinations, harmonies, trines, clashes, harms, punishments) found in a BaZi chart — and even says what is reported alongside each one (pillars involved, produced element). That is far more specific than the title alone. It stops short of differentiating itself from near neighbours such as astroway_bazi_four_pillars or astroway_bazi_chart, so an agent must infer the boundary.

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 when-to-use guidance, no prerequisite (a birth date/time is required by the schema but never mentioned), and no routing to or away from alternative BaZi tools. The only framing is the group/cost tag, which is metadata rather than usage guidance.

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