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 genuinely useful non-schema context: the 50-credit Tier 3 cost and the alias relationship to astroway_relational_synastry_attraction_score. It adds nothing about scoring caveats or reproducibility, so it is a modest positive rather than strong.

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?

The scoring formula is front-loaded in a single dense sentence, followed by short metadata lines for group, cost, and alias. Every line is informative; the alias note is slightly parenthetical but is useful for resolving the duplicate tool name.

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 a fully documented nested schema, an output schema, and rich annotations, the definition only needs to explain the metric itself, which it does precisely. The missing piece is comparative context against the sibling match-score and synastry tools.

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 100% and both nested chart objects are extensively documented in the schema itself, so the description needs to add nothing. It says nothing about chart1/chart2, fields, or precision, which is acceptable at full coverage but leaves this at the baseline.

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 computed artifact (weighted 0–100 attraction score) and enumerates the exact synastry contacts and house overlay that feed it, so an agent knows precisely what metric this returns. It does not explicitly distinguish itself from the sibling astroway_relational_match_score, which is the most likely confusion point, so it falls 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 when-to-use guidance, no prerequisites, and no routing to alternatives such as relational_match_score or relational_synastry. Only grouping and cost metadata are offered, which does not tell the agent when this tool is the right choice.

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