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

Annotations only declare that this is a non-read-only, non-destructive, closed-world write. The description adds substantial behavioral detail beyond that: payload shape (answers keyed by field key), the HMAC-SHA256 signing scheme and header name, the https-only constraint, the one-webhook-per-form limit, and the fact that signingSecret is returned only on this call. That is exactly the kind of context annotations cannot carry.

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?

A single dense sentence set that front-loads what gets created and the delivery contract, then tacks on the constraint, the uniqueness rule with its alternative, the return value, and the test path. No filler.

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?

There is no output schema, so the description correctly compensates by naming what is returned (the webhook, including signingSecret) and warning that the secret is shown only here. Combined with the delivery, signing and uniqueness details, an agent has everything needed to call it correctly.

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 75%, so the schema already documents url, headers and includeSchema. The description reinforces the public-https constraint on url and notes that answers are keyed by field key (relating to fields_list), but says nothing about the headers or includeSchema parameters, so it adds only marginal meaning beyond the schema.

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 — 'Create the webhook integration of a form' — and immediately describes the resulting behavior (submissions POSTed as JSON). It is clearly distinguishable from the sibling formWebhook_update, formWebhook_test and formWebhook_list tools.

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?

Explicitly routes to alternatives: 'one webhook per form (use formWebhook_update to change it)' and 'Verify delivery with formWebhook_test.' It also states the creation precondition that the endpoint must be public https, which is exactly the condition an agent needs before invoking.

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