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

Annotations already declare the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true, idempotentHint=false), so the bar is lower. The description adds genuinely useful operational data not in the annotations: the POST endpoint, the streaming group, and the 10-credit cost. However, it says nothing about how the stream delivers results (one-shot vs long-lived, cadence), which is the core behavioral question for a stream tool.

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 followed by compact bracketed metadata. Nothing is wasted, and the resource and scope land first. Slightly terse given the ten sibling stream tools, but structurally clean.

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 annotations cover safety. But the description leaves the streaming mechanics unstated and the latitude/longitude parameters undocumented, which is a gap for a tool whose entire value proposition is a stream rather than a single response.

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%: fields and precision are documented in the schema, but latitude and longitude have no descriptions anywhere. The tool description adds zero parameter meaning, so the undocumented coordinates are left entirely ambiguous for a tool that clearly needs an observer location.

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 resource (next solar+lunar eclipses) and scope (with totality info). An agent understands what it returns, but the description never names or contrasts with its closest sibling, astroway_stream_eclipse_incoming, so differentiation is left to inference.

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 and no mention of alternatives. The [Group: Real-time Streaming] tag hints at the streaming context but does not tell the agent when to pick this over eclipse_incoming or webhooks_eclipse_alert.

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