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

Annotations already declare readOnlyHint=false, destructiveHint=true, and idempotentHint=false, so the safety profile is provided. The description adds genuine operational context beyond those hints: "Changes can interrupt or redirect future deliveries." It still omits what specifically gets overwritten, auth/permission requirements, and reversibility, so it only partially exceeds the annotation baseline.

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 tight sentences, mutation intent front-loaded, followed by the impact warning. No filler. Slightly undermines itself by naming capabilities that aren't in the schema, which is a small precision cost rather than verbosity.

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?

It states the resource and the delivery-impact warning, but for a destructive 8-param mutation with no output schema and no parameter documentation, an agent still lacks field-level and prerequisite guidance. Adequate minimum, not complete.

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 0% across 8 parameters, so the description carries the full burden and does not meet it. It gestures at url, retry policy, and enabled state (and mentions two fields absent from the schema: subscriptions and signing), while omitting name, appId, endpointId, and rateLimitPerMinute entirely.

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?

Uses a specific verb ("Change") applied to a specific resource ("customer webhook endpoint") and enumerates the mutable facets: URL, subscriptions, signing, retry policy, enabled state. This is distinguishable from create_endpoint, delete_endpoint, and get_endpoint even though no sibling is named. Minor flaw: it lists "event subscriptions" and "signing settings" that do not appear in the input schema.

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?

No explicit when-to-use guidance, no alternative named, and no exclusion criteria among the many endpoint siblings (create_endpoint, delete_endpoint, rotate_endpoint_secret). The reader must infer this is the partial-mutation tool from the name alone.

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