Create email template

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

Annotations already declare non-read-only, non-idempotent, non-destructive, open-world behavior, so the bar is lower. The description adds non-obvious value by explaining the deferred effect ('Nothing is sent now: Pirate Ship uses the template when a label is bought with tracking emails on'), which clarifies the side-effect timing. Duplicate-name handling and permission requirements remain unstated.

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 core action, and every sentence carries real information about behavior. It is slightly redundant – 'Adds a tracking email template' and 'Saves a new tracking email template' restate each other, and the placeholder list repeats the schema verbatim.

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 must carry the return-value burden, and it never says what comes back (e.g., the created template's id) or how the call fails. The side-effect timing is well covered for a mutation tool, but duplicate-name behavior and the response shape are gaps an agent will notice.

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 71% and the description's placeholder list duplicates what html already documents in the schema, so most of the semantic load is already structural. Adding a 4 would overstate the contribution; a 3 understates it, because the placeholder enumeration does at least reinforce the one field an agent is most likely to get wrong. Score sits between, at 4 for reinforcing the highest-risk parameter.

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 (adds/saves) and a precisely scoped resource (a tracking email template used for tracking-link emails), and even clarifies what it does not do (send anything now). An agent can distinguish it from update_email_template, delete_email_template, and list_email_templates without opening any schema.

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 real usage context – the template is consumed when a label is purchased with tracking emails enabled, and nothing is sent at creation time. But it never says when to prefer this over update_email_template, what happens if a template with the same name exists, or whether prerequisites (e.g., tracking emails enabled) are required.

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