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

Annotations already declare readOnly=false, destructive=false, idempotent=false, openWorld=true. The description adds real value beyond them: the write has no outbound communication and no financial movement, and the customer number is auto-generated if omitted. It stops short of noting duplicate-name behavior or that creation is non-idempotent (which the annotations imply but the text never reinforces).

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?

Three short sentences, front-loaded with the verb, resource, and safety profile. The trailing 'POST /customers' is compact endpoint context with no wasted words.

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 17-parameter, nested-object write tool with no output schema and 35% param coverage, the description covers the essentials (purpose, required field, key side effects) but omits anything about the returned customer record/ID or duplicate handling. Adequate, but clearly incomplete.

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?

With 17 parameters and only 35% schema description coverage, the description carries a heavy burden but only touches two fields: name (required) and number (default generated, which the schema already states verbatim). No light is shed on type, currency, metadata, payment_terms, or the address fields.

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 opens with a precise verb+resource ('create a customer in Invoiced') and the 'WRITE:' tag immediately separates it from the many read-oriented siblings (get_customer, list_customers). An agent can pick this tool without opening the schema.

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?

It never states when to use this versus alternatives (e.g., create vs. get/list customer, or how to handle an existing customer). The remark that 'nothing is sent and no money moves' hints at low-risk usage but is not guidance about tool selection or preconditions.

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