Register Retrograde-Start Webhook

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

Annotations already declare non-read-only, open-world, non-idempotent, non-destructive behavior, and the description adds the useful cost figure (10 credits, Tier 1) plus the required field. It does not say whether repeated calls create duplicate subscriptions (relevant given idempotentHint=false), whether a delete/unsubscribe path exists, or what auth the POST needs.

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?

One sentence plus four compact bracketed metadata lines; every element (trigger condition, endpoint, required field, price) is load-bearing and front-loaded.

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, and endpoint/cost metadata covers the operational basics. What is missing is subscription lifecycle context – how many can be registered, how they are identified or removed – which matters for a mutating registration tool with no idempotency.

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 0% and the description contributes only '[Required: url]', repeating what the schema's required array already states. Neither source mentions the uri format or the 2048-char limit from the schema, and there is no hint about callback payload shape or verification handshake.

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 one-liner 'Fires when any of Mercury–Pluto stations retrograde' describes the trigger event, not the action; only the bracketed endpoint metadata (POST /v1/webhooks/retrograde-start) reveals that the tool registers a subscription. The title says 'Register', so the intent is recoverable, but the prose alone could be read as fetching retrograde data.

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 guidance on when to register this webhook versus the near-identical siblings astroway_webhooks_retrograde_end, astroway_webhooks_subscribe, or polling alternatives like astroway_stream_retrograde_alerts and astroway_calendar_retrograde_periods. The agent is left to infer selection from names.

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