get_fulfillment

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. It discloses that the tool returns 'full fulfillment' with specific fields, which goes beyond the name. While it does not mention error handling or authentication, the read-only nature is implied by 'Get', and for a simple fetch this is adequate.

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 efficient sentence that front-loads the core action and follows with useful return details. Every word contributes value, with no redundancy or fluff.

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 simple get-by-ID tool with one parameter and no output schema, the description adequately conveys purpose and return contents. It could be slightly more complete by explicitly noting it only returns one fulfillment and not a list, but overall it provides sufficient context for an agent to select and invoke the 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% since the only parameter, fulfillment_id, is described as 'Fulfillment ID (numeric). Required.' The description adds no additional meaning beyond the schema's clarification of the parameter, so it meets the baseline without enhancing parameter understanding.

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 clearly states 'Get a single fulfillment by ID' with a specific verb and resource, distinguishing it from sibling tools like list_fulfillments_for_order. It also specifies the return contents (tracking info, line_items, origin address), making the purpose 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 clearly implies the tool is for retrieving a single fulfillment when its ID is known. However, it does not explicitly mention alternatives such as list_fulfillments_for_order for listing fulfillments, nor does it state exclusions, so it lacks explicit when-not-to-use guidance.

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