Find Product by SKU

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering safety and idempotency. The description adds valuable behavioral context: that it returns specific base-table fields and does NOT retrieve EAV attribute values, instead directing to other tools. This goes beyond annotations without contradicting them.

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 sentences, front-loaded with the primary purpose and return fields, immediately followed by the precise alternative for EAV cases. No filler or repetition; every sentence earns its place.

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 simplicity (a single-lookup by SKU), the description covers the essential behavior, return fields, and the limitation regarding EAV attributes, with a pointer to the correct alternative. The presence of an output schema covers return format details. It doesn't enumerate every edge case (e.g., SKU-not-found behavior), but given the output schema and annotations, the description is adequate and above average.

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 description coverage is 100%, so the baseline for parameter semantics is 3. The description text adds meaningful context for the sku parameter ('Use find_product_by_sku instead of guessing EAV table joins'), reinforcing its role as the primary lookup key. This increment justifies a score above baseline, though not the full 5 since no extra semantics are provided for the other two generic parameters (profile, magentoRoot).

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 states a specific verb ('looks up'), a precise resource ('catalog_product_entity by SKU'), and lists the returned fields (entity_id, type_id, attribute_set_id, timestamps). This clearly distinguishes it from other find_* tools (e.g., find_order_by_increment_id) by the target entity and purpose.

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 when not to use this tool and what to use instead: 'For EAV attribute values use execute_select_query...' and 'Use get_eav_attribute first to find backend_type.' Also reinforces the sku parameter usage with 'Use find_product_by_sku instead of guessing EAV table joins.' This provides clear context, exclusions, and alternatives.

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