update_fulfillment_constraint_rule

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

With no annotations provided, the description carries the full burden, but it only states 'Update an existing fulfillment constraint rule' without disclosing mutation semantics, partial vs. full replacement, authorization needs, or response format. It adds no behavioral context beyond the operation implied by the name.

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 sentence with zero wasted words, making it concise. However, it's understandably short for such a tool, and the brevity may sacrifice useful context, but as a pure conciseness measure it's efficient.

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?

Despite having only 2 parameters and a schema, the lack of any explanation about what a fulfillment constraint rule is, what the update does, or what the response looks like, combined with no annotations or output schema, leaves the description incomplete for an agent to confidently invoke it. It only states the basic action.

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 both id and metafields are documented in the schema. The description adds no additional meaning beyond what the schema already provides, so the baseline of 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?

The description uses a specific verb ('Update') and resource ('fulfillment constraint rule'), and the word 'existing' distinguishes it from create/delete siblings. However, it doesn't clarify that updates are limited to metafields, leaving some scope ambiguity.

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?

No guidance is provided on when to use this tool versus create_fulfillment_constraint_rule or delete_fulfillment_constraint_rule. The only hint is 'existing', implying the rule must already exist, but there are no explicit exclusions or alternatives.

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