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

Annotations already declare readOnlyHint=false, destructiveHint=true, openWorldHint=true, and idempotentHint=false, so the safety profile is carried structurally. The description adds useful context about what the template is for, but says nothing about side effects an agent would care about — e.g., whether setting default=true displaces an existing default template, or whether the sender email must be pre-verified.

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 front-loaded sentence with no filler; the verb and resource come first and the use-case qualifier follows. Efficient, though it could have spent the same length on a more decision-relevant fact.

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?

A seven-parameter creation tool with no output schema, given only one sentence. It does not say what comes back (e.g., a template ID), whether the new template becomes active for new labels, or any constraints beyond what the schema enforces — significant gaps for a mutation with destructiveHint=true.

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%: html placeholders, name, default, bcc_email, and sender_email are all documented in the schema, and the description adds nothing further. Two required parameters (subject, sender_name) are undocumented but self-evident by name, so the schema still carries most of the semantic load — a baseline 3.

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?

"Adds a tracking email template" gives a specific verb plus resource, and the trailing clause explains what the resource is used for (recipient tracking-link emails). This distinguishes it implicitly from update_email_template, delete_email_template, and list_email_templates, though none are named.

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?

There is no guidance on when to use this versus update_email_template, nor on prerequisites such as needing tracking email settings configured or a verified sender. The only context is the purpose clause, leaving the agent to infer whether it should create a new template or modify an existing one.

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