update_custom_fulfillment_service

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

With no annotations provided, the description carries the full burden of behavioral disclosure, but it only states the action and resource. It does not disclose side effects, whether the update is partial or full replacement, error behavior, required permissions, or any other operational details. This is a significant gap for a mutation tool.

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 clear sentence with no unnecessary words or filler. It is appropriately sized for the simple purpose, front-loading the verb and resource. Every word 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?

The tool is relatively simple with a complete input schema, and the description gives a clear high-level purpose. However, it lacks behavioral context such as update semantics (patch vs replace), potential side effects, and response expectations. Given the absence of annotations and output schema, this is a minimal but not wholly inadequate description.

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?

The input schema has 100% coverage, with all five parameters having descriptions. The tool description adds no parameter-specific information, but since the schema already documents them, the baseline of 3 is appropriate. The description does not need to repeat schema details.

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 'Update an existing custom fulfillment service' uses a specific verb (update) and resource (custom fulfillment service), which clearly distinguishes it from sibling tools like create, get, and delete custom fulfillment services. It is specific and unambiguous.

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?

The description provides no guidance on when to use this tool versus alternatives, no prerequisites, and no context on how it fits into the broader fulfillment workflow. It does not mention any exclusions or specific scenarios, leaving the agent to infer usage from the name alone.

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