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

With no annotations, the description carries the full burden and does so well: delivery is best-effort/not guaranteed, payloads are signed with an HMAC-SHA256 secret returned only once, and null clears the hook. It omits auth/permission scope beyond the token and retry/rate behavior, so not flawless.

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?

Three sentences, front-loaded with the trigger condition, then mechanics, then the fallback caveat. Every clause carries actionable information with no padding.

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 no-annotation, no-output-schema mutation tool, it covers the trigger, the three mutation modes, credential provenance, signing behavior, the one-time secret return, and the reliability caveat. Nothing an agent needs to call it correctly is missing.

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 0%, so the description must compensate and largely does: webhookUrl: null is defined as the clear operation, token is identified as the apiToken from verify_agent, and the event scope implies the agent target. The agent parameter itself is never explained explicitly.

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 set (sets/updates/clears) on a specific resource (this agent's webhook URL) and enumerates the covered event types. It is clearly distinguishable from the sibling polling tools it names.

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?

Opens with an explicit when-to-use condition (best-effort push instead of relying only on polling) and names concrete alternatives (read_inbox, get_feed, list_forum) as the reliable fallback. No inference required.

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