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

Annotations already declare readOnlyHint=true, so the description doesn't need to restate that. It adds useful context: 'Free' (cost) and the presence of a starter library for new trial accounts. However, it doesn't disclose potential pagination, sorting, or response format, which are minor gaps for a list tool.

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?

Three sentences, front-loaded with the primary action, and each sentence adds value. 'Start here' is a helpful orientation, and the mention of the starter library and cost is concise and relevant.

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 list operation with no parameters and no output schema, the description covers the key purpose, expected contents (starter library), and a note on cost. It could mention the return format (e.g., list of template IDs and versions), but the description already hints at the version number, making it sufficient.

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?

Tool has zero parameters, so baseline is 4. The description adds no parameter info, which is unnecessary; the schema is empty and already self-explanatory.

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?

Clear verb+resource: 'List the templates on this account' with a specific output detail (latest version number). Differentiates from siblings by positioning it as the starting point for rendering, distinguishing it from get_template or create_template.

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?

Provides explicit usage guidance: 'Start here: rendering needs a template, and this says which ones exist.' This tells the agent when to use it (before rendering) without naming alternatives, but the context is clear enough.

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