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

With no annotations, the description carries the burden and does disclose the important trait: this makes a real outbound HTTP push to a live endpoint and returns the resulting status, so the agent knows it has external side effects. It leaves out failure/timeout handling, rate limits, and whether a webhook_url must be configured first.

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, action first, usage guidance second, zero filler. The side-effect nature and the returned value are both 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?

With no output schema, the description usefully states what comes back ('the HTTP status'). For a single-optional-param tool with no annotations the coverage is nearly sufficient; the gaps are preconditions (webhook_url must be configured) and error behavior on a non-2xx or unreachable endpoint.

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 there is only one optional parameter (api_key), so the schema does the heavy lifting and baseline 3 applies. The description never mentions api_key, and instead references 'webhook_url' and 'custom headers' that are not parameters, which implicitly tells the agent that config lives elsewhere but adds no parameter-level detail.

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 webhook.test event') plus the scope ('right now', 'to your webhook_url') and the outcome ('report the HTTP status'). No sibling tool does anything similar, so an agent can distinguish it immediately from update_agent or get_events.

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 names the trigger condition: 'Use after update_agent to confirm your endpoint receives pushes.' That is a clear when-to-use tied to a specific sibling. It does not state when NOT to use it or what to do on failure, which keeps it short of a 5.

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