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

Annotations already declare the safety profile (not read-only, open-world, non-idempotent, non-destructive). The description adds material context beyond them: the endpoint (POST /v1/webhooks/sign-ingress) and a cost of 10 credits (Tier 1), which is a genuinely useful operational trait. It does not explain lifecycle details such as what happens on re-registration, but the cost and endpoint additions are real value.

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 event trigger is front-loaded and the bracketed metadata lines are compact, scannable, and each carries useful facts (group, endpoint, required param, cost). No filler prose, though the lines are somewhat mechanical.

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 no explanation, but the definition never clarifies what 'tracked planet' means or how the subscription relates to the surrounding webhook-management tools. For a costed, non-idempotent registration call in a crowded sibling set, this is minimally adequate.

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 coverage is 67%: `fields` and `precision` are well documented with examples in the schema, but `url` is undescribed. The description's only parameter contribution is '[Required: url]', which merely restates the schema's required array and adds no meaning such as callback format or expected payload delivery behavior.

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?

Together with the title, the description states a specific event trigger (planet sign ingress) and the implicit action (register a webhook). It distinguishes itself from other webhook siblings by event type rather than by a generic 'webhook' label. It does not explicitly restate the verb 'register' in the description body, but the event scope is clear.

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 comparison to alternatives, despite many overlapping siblings (astroway_stream_ingress, astroway_webhooks_subscribe, astroway_webhooks_transit_trigger). The agent is left to infer that this is the webhook version of an ingress event versus a streaming variant.

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