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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds two useful bits beyond that: what the response contains and the negative constraint 'Secrets are never shown.' It stops short of noting auth or permission requirements, so a 3 is fair.

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?

One compact sentence with the resource and its contents front-loaded and the secrets caveat trailing. Nothing is wasted and nothing essential is buried.

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 output schema, the description compensates by listing the returned sections, which is the main thing an agent needs. Auth and error behavior are left to the schema and annotations, leaving only a small gap.

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%: instance_id's provenance and passport_token's header-vs-field fallback are both documented in the schema. The description adds no parameter meaning on top, so the baseline 3 applies.

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?

Clear verb (show/get) plus a specific resource (webhook inbox pro settings), and it enumerates the contents: upgraded inbox, forwarding with counts, signature preset, handshakes. It reads as a companion to inbox_pro_set, though it never names that sibling explicitly to force the contrast.

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?

No when-to-use guidance and no alternatives offered. An agent must infer from the name alone that inbox_pro_set is the mutating counterpart and that inbox_messages/inbox_bulk cover other inbox concerns.

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