Send a test event

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

Annotations already declare readOnlyHint=false, idempotentHint=false and openWorldHint=true, but the description adds the crucial fact that this is not a dry run — it goes through the real pipeline and is signed with the real secret, so an external receiver is actually hit. It does not mention rate limits, retries, or whether the test event appears in the subscription's delivery history except indirectly via list_deliveries.

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?

Two sentences, no filler, with the delivery mechanism and the safety rationale front-loaded before the follow-up action. Every clause carries information an agent would otherwise have to infer.

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 one fully documented parameter and no output schema, the description supplies what is missing: a live side effect on an external receiver, the returned eventId, and the natural next call. Nothing an agent needs to invoke it safely is absent.

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 100% and the single `id` parameter already carries an example and points to create_subscription/list_subscriptions. The description mentions webhookUrl and eventId but adds nothing about the `id` argument itself, so the baseline 3 applies.

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 and resource (send a signed subscription.test webhook), and pins down the mechanism: the real delivery pipeline, the subscription's real webhookUrl, its real secret, returning an eventId. That is far more distinct than the sibling subscription tools, none of which deliver anything.

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?

Gives an explicit when: prove the receiver and its signature check work before the first real change. It also names the follow-up step (call list_deliveries to see how the delivery went), so the agent knows both the trigger and the next call in the sequence.

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