list_templates

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds useful context about what the list contains and that it does not return template HTML, but it does not disclose behavior such as pagination, ordering, or whether the result set is limited or unbounded. The additions are modest but non-contradictory.

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?

The description is two sentences with no filler. The primary purpose is front-loaded, the returned fields are summarized compactly in parentheses, and the sibling tool is named in the second sentence. Every part of the description earns its place.

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 low-complexity list operation with one required parameter, no nested objects, and read-only/open-world annotations, the description provides sufficient context. It states what is returned, what is not returned, and how to access the alternative behavior. No output schema exists, but the simple metadata list is adequately described.

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%; the single parameter "account" is already described as "Account name" in the schema. The tool description only repeats the notion of a Klaviyo account without adding new semantic detail, such as whether account refers to an ID, slug, or display name. With full schema coverage, the baseline score of 3 is appropriate.

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?

The description opens with a specific verb and resource: "List email templates in a Klaviyo account," and further clarifies what kind of data is returned by naming the fields (name, editor type, dates). It also distinguishes itself from get_template by explicitly stating that get_template is for the HTML of a single template, making sibling differentiation immediate and clear.

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 explicitly tells the agent when to use get_template instead: "Use get_template for the HTML of one." This establishes a clear conditional routing rule. The tool's own use case, listing template metadata rather than content, is also concrete enough for an agent to select it appropriately.

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