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

Annotations already declare destructiveHint=true, so the safety profile is partly covered by structured data. The description adds real context — one application per call, optional event-type/channel narrowing, and the underlying REST verb/path — but says nothing about auth requirements, idempotency/duplicate-URL behavior, or what happens to an existing endpoint at the same URL.

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: purpose and scoping first, REST route second. No filler, and the most decision-relevant information (what is created, for which app, with what scope) is 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?

Seven parameters and no output schema, so the description carries more burden than it meets — notably it omits that creating an endpoint yields a signing secret the caller must retain, and gives no guidance on the disabled-first pattern. It covers the create action adequately but leaves the agent without the post-call essentials.

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 every parameter (uid, url, app_id, channels, disabled, description, event_types) is documented in the schema itself. The description only restates the event-types and channels scoping already present there, adding no syntax, format, or constraint detail beyond it.

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 concrete verb (Register), the resource (a webhook endpoint URL), and the scope (one application, optionally narrowed by event types and channels). The verb+resource pair is unambiguous against siblings like svix_get_endpoint or svix_list_endpoints, though no sibling is named 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?

The description says what gets registered but never states when to reach for this tool versus svix_get_endpoint, svix_list_endpoints, or svix_recover_endpoint, nor any prerequisite such as the application needing to exist first. Usage is only inferable from the resource name.

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