Add a webhook

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

Annotations already declare the mutation profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true, idempotentHint=false), and the description adds real substance: the exact HMAC-SHA256 signature header formula, the timestamp component, which events are delivered, and the one-time secret disclosure that must be surfaced to the user. It does not cover delivery retry/failure behavior despite sibling tools like list_webhook_failures and replay_webhook_failures implying failures exist.

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 tight sentences that front-load the purpose, then the signature contract, then the secret caveat. The signature formula is dense but earns its space; the trailing 'Free.' is a one-word pricing note that is mildly out of place but harmless.

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 2-parameter mutation tool with no output schema, the description supplies what the response actually yields (a one-time secret) and the verification contract the caller needs. The main remaining gap is behavior on duplicate registration and how failures are surfaced, given non-idempotent semantics.

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%, so the params are already documented, but the description adds operational meaning beyond the schema: the generated secret is returned exactly once in this response and the user must store it, which materially changes how the agent handles the result. It also clarifies the URL must be public HTTPS, reinforcing the format constraint.

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?

The description opens with a specific verb and resource ('Register a public HTTPS URL to receive batch-completion and deletion events'), naming exactly which event classes trigger delivery. Combined with siblings list_webhooks and delete_webhook, an agent can immediately distinguish creating a hook from listing or removing one.

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?

Usage context is implied by the event types (subscribe to batch completion/deletion), but there is no explicit when-to-use or when-not guidance, and no reference to siblings such as list_webhooks to check for an existing registration before creating a duplicate. The agent must infer placement from the name and event list.

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