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

Annotations already declare destructiveHint=true and idempotentHint=false, so the safety profile is covered. The description adds useful context beyond that: the endpoint must be Nilyo-owned (not the remote endpoint), the concrete consequence is halting future realtime delivery, and user intent must be explicit. It omits whether the deletion is reversible or what happens to queued deliveries, keeping it from a 5.

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 tightly written sentences with zero waste. The action is front-loaded, followed by the operational consequence and the intent requirement in priority order.

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 single-parameter destructive tool with rich annotations and no output schema, the description covers what is being deleted, the ownership scope, the delivery-stopping effect, and the intent prerequisite. It is nearly complete; only the permanence/reversibility of the deletion is left unstated.

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 single destination_id parameter is fully documented in the schema, including the warning to use the Nilyo destination ID rather than the remote endpoint ID. The description adds no parameter-level detail, 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 ('Delete an Nilyo-owned webhook endpoint') and immediately scopes the effect ('stops future realtime delivery'). It is unmistakable against siblings like webhook_update_destination or webhook_get_destination.

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?

Provides a clear usage directive: 'require explicit user intent,' which is strong guidance for a destructive operation. It does not, however, name alternatives (e.g., use webhook_update_destination to disable instead of delete), so it stops short of explicit when-not guidance.

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