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

Annotations already declare readOnlyHint=false, openWorldHint=true, non-idempotent and non-destructive, so the safety profile is covered. The description adds genuinely useful context the annotations lack — the 10-credit Tier 1 cost — but says nothing about streaming semantics, latency, or whether the call is a one-shot snapshot or a subscription.

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 front-loaded sentence plus two bracketed metadata tags — no filler. It is efficient, though the bracketed cost/group lines carry more weight than the actual capability sentence.

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 described. But for a location-aware streaming tool with four parameters and a nearly identical sibling, the definition omits location semantics, streaming behavior, and any disambiguation, leaving the agent under-equipped to call it correctly.

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?

Latitude and longitude carry no schema descriptions, so half the parameters are undocumented in both schema and description. The description never explains whether a location is required for totality visibility, nor what fields/precision do beyond the schema's own text.

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 (next solar+lunar eclipses) and a distinctive attribute (totality info), which is more specific than the typical eclipse sibling. However, it does not distinguish itself from astroway_stream_eclipse_incoming, which almost certainly also returns upcoming eclipses, leaving the agent to guess which eclipse tool to pick.

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?

No when-to-use statement, no prerequisites, and no reference to alternatives such as astroway_stream_eclipse_incoming or the webhook-based astroway_webhooks_eclipse_alert. The only context given is a group tag and a cost tier, which is not usage guidance.

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