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

No annotations are supplied, so the description carries the burden. 'List' implies a non-mutating read and the sentence discloses the returned fields (size, slots), but it says nothing about auth requirements, pagination, ordering, or list size. Adequate for a low-risk read, but not rich behavioral disclosure.

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 short sentences, the purpose is front-loaded, and the second sentence carries actionable sequencing guidance. Nothing is redundant or padded.

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 one-optional-parameter read tool with no output schema, the description covers what is returned and when to call it, which is enough to invoke correctly. Only minor gaps remain, such as whether results are paginated or ordered.

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?

The description never mentions the optional 'tag' parameter, so it adds no meaning beyond the schema. However, schema description coverage is 100% and the parameter's own description already explains the filter with concrete examples, so the baseline of 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?

States a specific verb and resource ('List Platemark image templates') plus the payload the caller gets back ('size and the slots each one takes'). That is clearly distinct from the sibling tools account_status, create_account and render_image, so an agent can select it without opening the schema.

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?

'Call this first to pick a template and see slot names' gives explicit ordering guidance, implicitly positioning it ahead of render_image. It stops short of stating when not to use it or how the optional tag filter changes selection, so it is strong context rather than a full when/when-not rule set.

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