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

Annotations already establish readOnlyHint, idempotentHint, and destructiveHint. The description adds useful context beyond those annotations by clarifying the data is first-party product content with no tenant data, which helps an agent understand access implications without contradicting the annotations.

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?

Two tightly written sentences with no filler. The main action and scope come first, followed by a read-only clarification and sibling routing, making every sentence earn 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 read-only listing tool with no output schema, the description lists the returned fields, notes the lack of tenant data, and names the follow-up actions with template_get and zpl_preview. Combined with annotations and full schema coverage, nothing essential 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 the schema already documents both parameters (substring match on id/tags; category filter with enum). The description does not add significant parameter-level detail beyond this, so the baseline 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 names a specific verb ('List'), a resource ('first-party label template catalog'), and the key fields returned (id, name, category, size/density, tags). It also differentiates this listing tool from template_get and zpl_preview, so an agent can distinguish it from its siblings.

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 clearly signals this is the tool for browsing the catalog and product content, not tenant data. It explicitly points to template_get for fetching a single template and zpl_preview for rendering, which gives an agent a clear routing cue, though it does not enumerate exhaustive when-not-to-use conditions.

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