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

Annotations already indicate readOnlyHint and openWorldHint, but the description adds valuable behavioral context: it details the exact response structure, the distinction between surfaces and category slugs, and that surfaces are product-bound. No contradictions exist; the description enriches the annotated safety profile.

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 a single, dense paragraph that front-loads the purpose and usage, then provides a structured response summary. Every sentence serves a purpose—scope, timing, content, and a correction—without fluff. It is long but justified for an entry-point tool with substantial output.

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?

Given the tool's complexity (extensive return data) and the presence of an output schema, the description nevertheless provides an explicit response shape, clarifies key semantics, and ties to siblings. An agent can confidently call it first and understand the result structure without further lookup. Nothing essential is missing.

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 by the rule, the baseline is 4. The description correctly notes 'Parameters: none' and focuses on the output, which is entirely appropriate. No parameter explanations are needed.

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 it is the 'single call this first entry-point' that 'briefs an agent on the entire Revuo directory' and lists exactly what it returns (taxonomy, counts, flags, surfaces, etc.). It distinguishes itself from siblings by naming the subsequent tools it feeds, making its role 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?

Explicitly instructs 'Use this once at the start of a session to ground every subsequent products.search / products.find_by_capability / tools.find_for_task call.' It also clarifies a common pitfall (surfaces are not category slugs), preventing misuse and guiding correct routing to alternatives.

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