Sandbox Trigger Webhook

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

Annotations already declare readOnlyHint=false, destructiveHint=true and idempotentHint=false; the description adds the crucial context that this is sandbox-only, requires a sandbox key, and actually emits a signed delivery to registered live endpoints (the source of the destructive/ non-idempotent profile). It does not say whether deliveries are recorded as real webhook deliveries or how to inspect their outcome.

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?

Front-loads the decisive constraint (SANDBOX ONLY) and keeps the rest to two short sentences; the em-dash clause earns its place by explaining why cron-driven events need a synthetic trigger. Slightly dense but no filler.

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 no output schema, the description still covers environment, auth, prerequisite setup and intended use, which is nearly everything needed to call it. The remaining gaps are return/observability (what the call returns, how to see the resulting delivery) and disambiguation from test_webhook/resend_webhook.

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 the enum is fully documented with per-value descriptions, so the schema carries the parameter burden. The description reinforces that eventType accepts any enum value including cron-driven ones, but adds no format or default details beyond the schema.

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 verb+resource ('Fire a sample signed webhook event to your registered endpoints') plus scope ('SANDBOX ONLY') and the unusual capability (any event type, including cron-driven events that don't come from an API call). An agent can distinguish it from the other webhook-delivery siblings.

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?

Explicitly covers prerequisites: register an endpoint first with the webhook tools, and a sandbox API key (pk1_sb_…) is required, plus the use case (testing your handler and HMAC verification). It does not, however, contrast itself with the near-neighbor siblings test_webhook and resend_webhook, which an agent could easily pick by mistake.

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