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

Annotations already declare readOnlyHint/destructiveHint, but the description adds real behavioral facts: results are most-recently-changed first, archived templates are excluded, all matches come back in one answer (no pagination), an empty list signals no match, and a null published_version means render cannot use it. It also notes the call is free, which matters for an agent deciding whether to probe.

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 purpose and scope, and every clause carries information an agent would otherwise have to guess. The single dense block runs long and chains several ideas, but there is no filler sentence to cut.

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 an output schema present the description needn't enumerate return values, yet it still calls out ordering, archived exclusion, and the published_version null edge case that gates render. Combined with 100% schema coverage and clear annotations, an agent has everything needed to call this correctly or decide not to.

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 q, tag, kind and engine are already fully documented, including case-insensitivity, exact-match tag format, and the kind/engine enums. The description's brief gloss of kind values repeats the enum rather than adding filtering semantics, so the baseline 3 applies.

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?

Specific verb (Lists) plus resource (templates) plus scope (the workspace this server works in, chosen at sign-in or the API key's), ordering rule, and the returned field set. It also names the siblings that consume the slug (get_template_schema, validate_template, render), so an agent can place it precisely in the workflow.

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?

Explicit when: "Call it first to find the slug that get_template_schema, validate_template and render take." Explicit when-not: "skip it when the user already named the template." Both the trigger and the exclusion are stated, not implied.

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