ecommerce_updateProductVariantsInBatchV1

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

With zero annotations, the description carries the full burden of behavioral disclosure and does so well: 'in place by id' (idempotent-style update), 'up to 100' (hard limit), 'omitted variants left untouched' (partial update), 'prices replace existing in full' (replacement, not merge semantics), and 'returns updated variants' (return contract). Gaps: no error behavior for non-existent variant_ids, no atomicity guarantee, no auth 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?

Five tight sentences, each adding distinct information: scope/limit, fields, partial-update behavior, price replacement semantics, and return value. No filler. Slight redundancy between 'omitted variants left untouched' in the description and the same note in the variants param description, but this is a minor overlap.

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 batch mutation with no annotations and no output schema, the description covers limits, partial update semantics, price replacement, and return value — solid groundwork. However, it omits critical operational context for a batch write: what happens on partial failure (atomic all-or-nothing vs. per-item success), and how non-existent variant_ids are handled. These are exactly the questions an agent must answer before safely calling a batch mutation 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?

Schema coverage is 100%, so baseline is 3. The description earns a 4 by clarifying the non-obvious semantics of the `prices` parameter — that it fully replaces existing prices — and clarifying that the variants array itself is a partial update (omitted fields untouched). These are exactly the behavioral nuances the schema alone doesn't convey.

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?

Clear specific verb ('Update'), resource ('existing variants'), and scope ('up to 100... in batch by id'). The description names the exact fields affected (title, inventory, stock tracking, prices). Loses a point for not explicitly distinguishing from any sibling tool, though the batch/limit semantics make it hard to confuse with the single-item create/update variants.

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?

Implies usage context through 'in place by id' and 'up to 100' batch semantics, and clarifies partial-update behavior with 'variants omitted from the request are left untouched.' However, it never explicitly states when to prefer this over single-variant update tools or how to handle the 100-item ceiling (split into chunks?). Context is implied, not stated.

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