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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds the useful scope fact that these templates are global/unfiltered, but says nothing about pagination, result volume, or auth beyond the apiKey parameter.

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 sentence with zero filler, and the distinguishing scope qualifier is placed at the end where it reads naturally. Appropriately sized for a trivial list operation, though it is so terse that it borders on under-specification.

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?

For a simple, annotation-rich read-only list tool with no required parameters, the description covers what an agent needs to select it. The only minor gap is that no output schema exists and the description says nothing about return shape or pagination, though this is inferable for a catalog listing.

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?

Single parameter (apiKey) with 100% schema description coverage, so the schema already documents it and the description adds nothing parameter-specific. Baseline 3 is appropriate when the schema does the heavy lifting and the description does not compensate with extra meaning.

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 ('List') and resource ('starter-gallery email templates') with explicit scope ('available to every workspace'). This scope wording implicitly separates it from list_workspace_templates, but no sibling is named outright, so it falls just short of a 5.

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?

Usage is only implied: the phrase 'available to every workspace' tells the agent this is the unfiltered global catalog, but the description never states when to prefer it over list_workspace_templates or get_template, nor any prerequisites. No explicit when/when-not guidance is present.

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