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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered elsewhere. The description's one genuine addition is operational: 'Cost: 10 credits (Tier 1)', which is not in any structured field and matters for budgeting calls. It says nothing about output content, precision defaults, or why an ayanamsa/houseSystem would matter here.

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?

It is short with no filler, and the metadata lines (group, cost, alias) are scannable. But the brevity is largely under-specification rather than efficiency: the lead line is a noun fragment and no sentence actually describes a callable operation.

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?

For a 15-parameter tool with only 33% schema description coverage, the definition omits what the result contains (beyond the existing output schema), how the required moment inputs should be supplied, and how this technique relates to its many Hellenistic siblings. Group, cost, and the alias are present, but the core question of what calling this produces is left unanswered.

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 covers only 33% of 15 parameters, and the description adds zero parameter meaning. Undocumented fields such as `name`, `city`, and `cosmogram` remain ambiguous, and the description does not clarify that date/time/latitude/longitude are mandatory birth-moment inputs or how zodiacType/ayanamsa interact with a sidereal constellation technique. With low coverage, the description is expected to compensate and does not.

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 fragment 'Constellations beyond the zodiac' conveys the domain (extra-zodiacal constellations in the Greenbaum Sphaera Barbarica tradition) but names no verb, no output, and no computation, so an agent cannot tell what it actually returns. It does explicitly identify itself as an alias of `astroway_hellenistic_greenbaum_sphaera_barbarica`, which resolves duplication against that one sibling, but nothing distinguishes it from the other Hellenistic Greenbaum tools aside from the group tag.

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 statement, no prerequisites, and no comparison to related Hellenistic tools (zodiacal_decans, temple_doctrine, dodekatemoria). The only routing hint is the alias note, which tells the agent it is interchangeable with the canonical Greenbaum endpoint rather than when this technique is the right one.

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