wafeq_bills_line_items_partial_update

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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false; the description merely restates that this is a write operation using PATCH. It adds no context about side effects, authentication requirements, or how omitted fields behave in a partial update.

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 opening line is front-loaded and compact, using clear signals like 'WRITE', 'PATCH', and the resource path. However, 'Partial update bill line item' and 'Endpoint for partially updating an existing bill line item' are near-identical restatements, making the description redundant despite being short.

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 nested-object partial update with no output schema, yet the description only identifies the endpoint. It omits how partial update semantics work, what a successful response looks like, and any prerequisites or side effects. The detailed input schema partially compensates, but the description itself is not complete enough for reliable invocation.

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 only 50%, and the tool description does not clarify the path parameters bill_id and id, the body structure, or the confusing body description about augmenting custom_fields. The nested field schemas provide some value, but the description itself adds no parameter-level meaning.

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 names the verb ('partial update'), the resource ('bill line item'), and the HTTP method (PATCH), so an agent can tell what action is being performed. It does not explicitly distinguish this from the sibling full-update tool wafeq_bills_line_items_update, so it stops short of a 5.

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 explicit guidance about when to choose this tool over alternatives like wafeq_bills_line_items_update or wafeq_bills_line_items_create. The phrase 'partial update' implies only a subset of fields will be changed, but the description leaves the selection logic entirely to the agent.

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