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

Annotations already declare readOnlyHint=true and openWorldHint=false, so "Free, read-only" mostly repeats structured data. The genuinely additive parts are the returned field list and the partner-only access tier, though the latter is unactionable because no partner_key parameter exists in the schema.

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, front-loaded sentences with no padding; the resource and return fields come first, constraints second. The "etc." and parenthetical example are slightly loose but cost little.

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 no output schema, the description usefully enumerates the fields returned and answers the access-tier question for a simple read tool. The remaining gap is the unsupported partner-key requirement, which is stated but cannot be acted on with the given parameters.

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 coverage is 100%, so both optional filters (country, changed_since) are already documented. The description adds no syntax, format, or defaulting detail beyond what the schema provides, so 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?

States a specific verb+resource ("List fillable standard document templates") with concrete examples and the fields returned (version, last_verified, updated dates). An agent can immediately tell this is the discovery tool that pairs with the sibling fill_template, rather than the filling action itself.

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?

"Free, read-only" and "Partner-only templates need the partner key" give some usage context, but the description never explicitly says when to use this versus fill_template, nor does it name the sibling. It also doesn't explain how a partner key would be supplied, and the described condition cannot be satisfied with the exposed parameters.

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