update_purchase

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

No annotations are provided, so the description carries the full behavioral burden, yet it only implies mutation via the word 'update'. It does not say whether this is a partial patch or a full replace of the purchase record, which fields are mutable, whether line items are replaced wholesale, whether synchronization tokens or optimistic locking apply, or what side effects occur on linked transactions.

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?

One short, front-loaded sentence with no filler or repetition, which is structurally clean. But it is under-specified rather than concise — the brevity comes at the cost of any actionable detail, so it cannot rate higher on structure quality alone.

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?

This is a mutation on a nested-object entity with zero schema documentation, no annotations, and no output schema. For that complexity level the description should at minimum identify the identifying parameters and the update semantics; it provides none of this, leaving the agent unable to construct a correct call from the description alone.

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 0% and the single parameter is a nested, untyped object requiring a 'purchase' property whose shape is entirely undocumented. Given that QuickBooks typically requires Id and SyncToken plus the modified fields, the description supplies no field names, formats, or required identifiers, so it fails to compensate for the schema gap.

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 the verb 'update' and the resource 'purchase' with the product context (QuickBooks Online), so the basic action is identifiable. However, the sibling set contains update_purchase_order, update_payment, update_bill and update_vendor_credit, and a 'purchase' in QuickBooks is a distinct transaction entity from a purchase order — the description does nothing to disambiguate these, so an agent must guess from the name alone.

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?

There is no indication of when to use this tool versus update_purchase_order or update_payment, no prerequisites (an existing purchase id, SyncToken, permissions), and no note that create_purchase/get_purchase are the counterpart operations. The agent is left to infer the entire workflow.

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