products_update

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

Annotations already cover the safety profile (not read-only, idempotent, non-destructive). The description adds genuinely useful behavior: partial-update semantics ('all fields are optional — only provided fields are changed') and the null-clearing convention, which is not obvious from the annotations alone. It remains silent on validation failures or permission requirements.

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?

Three sentences, identity and partial-update contract front-loaded, then use cases, then the null edge case. The parenthetical about grouping sales per plan/SKU justifies its length.

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 16-parameter mutation tool with full schema coverage, no output schema, and annotations carrying safety, the description supplies exactly the missing pieces: partial update, null-clearing, and realistic usage contexts. Nothing an agent needs to call it correctly is absent.

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 every parameter including null-clearing is already documented in the schema. The description reinforces the partial-update and code=null behavior but adds no parameter detail the schema lacks, so baseline 3 is appropriate.

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 and resource ('Update an existing product by UUID'), which is unambiguous against products_list/products_get and the category tools. It never names a sibling explicitly, but the resource is narrow enough that confusion is unlikely.

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?

Gives concrete use cases (assigning SKUs so sales group per plan, fixing names, adjusting prices on sync-created products), which tells an agent when this is the right call. It does not say when to reach for products_get or product_categories_update instead, so there is no explicit exclusion guidance.

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