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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It does reveal a key trait: partial updates ('Only the fields you pass are touched'), which is valuable. However, it omits other behaviors like validation rules, error handling, or permission requirements, leaving gaps.

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 description is concise at two sentences, front-loading the core action and then the partial-update behavior. It has no filler and is easy to parse, though it could be slightly more structured by enumerating example parameters.

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?

Given no annotations, no output schema, and 0% parameter coverage, the description is incomplete. It only covers the update semantics but lacks information about required fields, input formats, return values, or error conditions, which an agent would need to call it correctly.

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 description adds no parameter-specific information. It does not explain what 'id', 'notes', 'taxId', 'currency', etc. represent or how they should be formatted. This is a significant deficiency for a 7-parameter tool.

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 states the verb 'Change' and the resource 'billing profile', and it implicitly differentiates from sibling tools like billing_profile_create and billing_profiles_get. It does not list specific fields, but the schema provides them, so the purpose is unambiguous.

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 on when to use this tool versus alternatives, such as when to create a new profile or list existing ones. The description implies it is for modifying an existing profile but does not state prerequisites (e.g., that an ID is required) or conditions for choosing it over other billing-related tools.

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