update_billing_client

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

Annotations already declare the safety profile (readOnlyHint=false, openWorldHint=true, destructiveHint=false), so the description's main added value is confirming the mutation targets an external billing module (whmcs/update_client). It says nothing about partial-update semantics, reversibility, or auth needs, so it adds only modest context beyond the annotations.

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?

A single front-loaded sentence with the verb, resource and backend path leading. No filler, though the trailing 'etc.' is slightly sloppy.

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 12-parameter mutation with no output schema and near-zero schema coverage, the definition omits critical behavior: whether omitted fields are left unchanged, whether the whole record is overwritten, and how errors surface. This is a significant gap for an update operation.

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 8% (only 'confirm' is documented), so the description must compensate. The field list (name, company, address, email, phone) maps loosely onto the billing_* parameters but uses generic terms and 'etc.' rather than matching parameter names, leaving the correspondence inferential.

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 a specific verb and resource ('Update client data in billing') plus the backend module (whmcs/update_client), and enumerates the main fields touched. It implicitly distinguishes itself from the sibling get_billing_client, though it never names it explicitly.

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?

Only implies usage through its verb. There is no statement of when to use this versus get_billing_client, whether the client must already exist, or any prerequisite/authorization context.

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