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

With no annotations, the description must carry the burden of behavioral disclosure. It states what is included (coverage, completeness, last read) and explicitly excludes contact details, but it does not disclose whether the operation is read-only, requires authentication, or has side effects. It also hints at server instructions but doesn't elaborate. This is partially transparent but not comprehensive.

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?

The description is two sentences with no wasted words. The primary function is stated first, followed by a clear limitation. It is concise, front-loaded, and avoids redundancy.

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 tool with no parameters and no output schema, the description adequately conveys what the tool returns and what it omits. It covers the essential information an agent needs to decide if this tool is appropriate. It could mention the response format (e.g., array) but that is a minor gap given the simplicity of the tool.

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 tool has zero parameters, so the schema provides no parameter info. Per the rubric, the baseline is 4 for 0 params. The description adds value by specifying the output content (what data each supplier entry includes), which is more than the empty schema conveys. No parameter semantics are needed since there are none.

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 clearly states the function: it lists every supplier on file and specifies the data returned (coverage, completeness, last read). It distinguishes itself from siblings like get_brand (specific brand) and compare_brands (comparison) by covering all suppliers. The verb 'list' and resource 'suppliers' make purpose unambiguous.

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 implies usage for retrieving all suppliers but does not explicitly name alternatives or conditions for when to use this vs. other tools. The note 'No contact details — see the server instructions' provides an exclusion but no explicit pointer to a specific sibling. It gives context but lacks clear when-to-use/when-not-to-use guidance.

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