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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description correctly adds that it's a 'Public read' with optional auth_token, which is useful context. The return structure is disclosed. Minor deduction for not explicitly stating rate limits or parallel execution details, but the description adds good value on top of annotations.

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 dense but the last sentence is essentially a duplicate of the tool name and adds bulk without much value. The rest is well-structured and information-dense, front-loading the key grouping behavior before diving into return shapes.

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 moderately complex multi-tenant search tool with 5 params and no output schema, the description covers the key semantic behavior (grouping), input source, output shape, error wrapping, and example invocation. No critical gaps identified.

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 baseline is 3. The description adds significant semantic meaning by explaining what 'grouped' means ('collapses size/color variants into one row'), describing the return shape (priceRange, variantCount, options, nested variants), and explaining the relationship to the alternative tool. The example helps invoke correctly. Minor deduction because the limit parameter semantics ('Maximum variants to fetch per tenant before grouping') could be further clarified, but overall strong param explanation.

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 tool searches product FAMILIES (grouped variants) across multiple tenants. It explicitly distinguishes itself from siblings like federation_catalog_search_multi (for exact variant SKUs), making the purpose and differentiator unmistakable.

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 when-to-use guidance ('Prefer this for discovery'), names the alternative tool for exact SKUs ('Use federation_catalog_search_multi when you need exact variant SKUs'), and explains where tenant_ids come from (federation_list_tenants or 'all'). This is exemplary guidance.

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