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

Goes well beyond the readOnlyHint annotation to disclose a non-obvious behavioral rule: the webhook signing secret is never returned to an API key, the response reports webhook.secret_set instead, and the raw value is only visible in the dashboard or in the update_settings response that created or rotated it. It also states the auth requirement, which annotations do not cover at all.

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?

Front-loaded with the primary payload description before the subtlety about the signing secret, and the update_settings cross-reference is placed exactly where it matters. The second ACCESS paragraph is somewhat operator-specific (Claude Code /mcp flow) but is genuinely actionable rather than 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?

With no parameters and no output schema, the description carries the full burden of describing the return shape, and it does: webhook endpoint, event subscriptions, proof lifetime, and the secret_set substitute field. An agent knows what it will receive and what it will not.

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?

The tool takes zero parameters, so the schema has nothing to explain and the baseline is 4. The description correctly adds no parameter narrative where none is needed.

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 (get) and resource (account settings) and enumerates exactly what is returned: the outbound webhook endpoint with its event subscriptions and the default proof lifetime. It also explicitly carves out branding as belonging to the sub-account and points to the sibling get_profile, so an agent can separate this tool from the many other 'get_*' tools in the list.

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?

Gives clear routing guidance (branding → get_profile) and a concrete precondition for calling it at all: a Proof account plus client authentication, with the explicit warning that start_login does NOT open this tool. It lacks an explicit 'use this when you need X' framing for the settings themselves, but the access prerequisites and the sibling exclusion are strong.

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