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

Annotations already declare readOnlyHint=false with destructiveHint=false, so the agent knows this is a non-destructive write. The description adds real value beyond that: it specifies the result is a DRAFT, that nothing is dispatched until review and publish, and that a review link is returned. That is exactly the mutation-side-effect disclosure the 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?

Three short sentences, each load-bearing: the action and its output state, the return value, and the safety guarantee. The most important fact (a draft is created, not a send) is front-loaded. Zero 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 an output schema present for the review link, 100% parameter coverage, and annotations covering the safety profile, the description only needs to close the remaining gap — which it does by pinning down the draft/publish lifecycle. Nothing an agent needs to invoke this 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 description coverage is 100%, so all five parameters including channel, brief, slug, description and the context-intent field are documented in the schema itself. The description restates the channel list ('email, SMS, push, or web-push') and the brief concept but adds no syntax, defaulting, or format guidance beyond what the schema already provides. 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?

Specific verb-and-resource: 'Generate a new email, SMS, push, or web-push template from a plain-language brief', plus the resulting state ('save it as a DRAFT'). An agent immediately knows what this does and what it produces. It does not, however, explicitly contrast itself with the close sibling senderkit_templates_regenerate, so sibling differentiation is left implicit.

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?

The description implies usage context ('from a plain-language brief', 'Nothing is sent until the user reviews and publishes the draft') which signals when this tool is the right choice over senderkit_send. But it never states when to prefer this over senderkit_templates_regenerate, nor any prerequisite for the brief/context inputs. Usage is implied rather than instructed.

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