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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds conceptual behavior — that the result is split into a meridian term and equation of time, and that it can shift the hour pillar — which is useful context beyond the annotations, but it says nothing about precision limits, error cases, or dependence on the timezone/longitude inputs.

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?

Front-loaded with the core definition followed by one well-chosen illustrative example; the group and cost lines are metadata. Every sentence carries weight, though the example is slightly expansive.

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 return values need not be explained, and the annotations cover safety. However, with 8 parameters at 50% coverage and no usage guidance, the definition leaves the agent to infer when and with what inputs to call it, which is a meaningful gap for a computation tool.

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 50%, with date, time, longitude and language left undocumented in the schema. The description conceptually anchors the longitude input ('corrected to the sun over the birth longitude') and the timezone issue, but it adds no format or syntax detail and never mentions the compact-mode fields/precision parameters, so it only partially compensates for the coverage gap.

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 computation — the clock corrected to the sun over the birth longitude, decomposed into meridian term and equation of time — so the agent knows this converts clock time to true solar time rather than producing a chart. It does not explicitly differentiate itself from related siblings like astroway_bazi_hour_pillar, which it only alludes to via 'which moves the hour pillar'.

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 explicit when-to-use statement, no prerequisite guidance, and no named alternative. The Kashgar example implies the tool matters for Bazi hour-pillar accuracy, but the agent must infer that context rather than being told to reach for this before a Bazi computation.

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