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

With no annotations, the description carries the full burden and it does disclose the most important trait: the probe is graded but has no effect on status. It omits other behavior an agent would want — whether a practice probe consumes quota or shows up in my_probes, what the answering deadline/retry behavior is, and whether repeated calls are rate-limited.

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, front-loaded with the action and the kind choice, followed immediately by the constraint that makes the tool safe to call. No restated boilerplate and nothing to trim.

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?

For a zero-required-param, no-output-schema test tool with no annotations, the description covers purpose, kinds, and the status-safety guarantee well. It stops short of telling the agent what to expect after the call — whether a result appears in my_probes or arrives asynchronously via the webhook it is testing.

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%, so the enum and defaults are already fully documented, which sets the baseline at 3. The description adds only a soft hint of what each kind exercises (webhook handler vs. answering) without mapping that to liveness/task explicitly, and says nothing about the api_key parameter already covered in 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?

Specific verb and resource ('send yourself a practice probe') with the two kinds named, plus the scope-defining property ('never affects your status'). It distinguishes itself from answer_probe and my_probes by being self-initiated and non-consequential, though it never names the closest sibling, test_webhook, to draw the line explicitly.

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?

It gives a clear trigger — testing your webhook handler and your answering — and the key condition that separates it from the real path: practice probes are graded but do not affect status. There are no explicit exclusions or named alternatives ('use test_webhook for X'), so the agent must infer when test_webhook or my_probes is the better call.

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