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

With no annotations, the description must carry the behavioral load. It does disclose the key outcome ('Returns the new client id') and the ordering constraint, which is genuinely useful. But it says nothing about permissions, duplicate-email handling, or whether repeated calls create duplicates — significant gaps for a write tool with zero annotation coverage.

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, each earning its place: the action, the business prerequisite, and the return value. Front-loaded and waste-free.

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 four-parameter create with a fully documented schema and no output schema, the description covers the action, prerequisite, and return value. Missing duplicate/uniqueness behavior and error cases keeps it from a 5.

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 100%, and the schema itself spells out name, email, notes, and company semantics, so the baseline is 3. The description adds no parameter-level detail beyond what is already structured.

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: 'Create a customer record.' Combined with the note that a client is a prerequisite for an invoice, an agent can tell this apart from invoiceflow_create_invoice and invoiceflow_list_clients. It stops short of explicitly naming those siblings as alternatives.

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?

'A client is required before an invoice can be created' gives a clear condition that triggers use of this tool. There is no guidance on the reverse case (e.g., checking list_clients for an existing record before creating a duplicate), so work is left to inference.

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