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

Annotations already declare destructiveHint and idempotentHint, so the safety profile is covered. The description adds real context beyond that: the concrete consequence ("Events stop being delivered to that URL") and the precise semantics of the idempotency (deleting a missing hook still succeeds). It does not mention confirmation requirements or reversibility, which would be needed for 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?

Three short sentences, zero filler, with the destructive effect and idempotency stated up front rather than buried. Every sentence carries distinct information.

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?

A single-parameter mutation tool with full annotation coverage and an output schema needs only what is here: what it removes, the side effect, and the idempotency contract. 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 100% and the schema already states the id is a uuid from list_hooks, so the description's parenthetical adds nothing new. With the schema doing all the work, baseline 3 is appropriate.

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?

"Remove a webhook subscription by id" states a specific verb and resource, and the parenthetical routing to list_hooks separates it cleanly from create_hook and list_hooks. An agent can identify the tool's job without opening the 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?

It tells the agent where the id comes from (list_hooks), which is the main prerequisite for correct invocation. It stops short of explicit when-not-to-use guidance or a stated alternative, so it falls just below the top band.

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