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

Annotations supply only destructiveHint=true, so the description must carry the rest. It adds the valuable partial-update semantics (unmentioned fields are untouched) and the underlying REST verb/path. It does not disclose permissions/auth requirements, whether the operation is reversible, or what happens with an empty body, so it is only partially complete for a mutation.

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 mutation scope before the partial-update rule. The trailing "Housecall Pro: PUT /customers/{customer_id}" is slightly redundant but does anchor the operation to a known API surface, so little is wasted.

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 thin annotations, the description covers fields and the partial-update rule but leaves the return value, failure modes and auth requirements unaddressed. It is workable but not complete for a tool of this size.

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 33%, so the description must compensate, and it does partially by grouping first/last name, the four phone/contact fields, tags, lead source, notes and notifications_enabled into named concepts. It omits company entirely and gives no format expectations (e.g. phone formats, tags replace vs append), so the compensation is incomplete.

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?

Clear specific verb ("Change") plus resource (customer) and an enumeration of the mutable fields (name, contact details, tags, lead source, notes, notification setting). This clearly separates it from get_customer/create_customer. However, it never explicitly routes away from siblings, so it stops short of the top band.

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 the fields you pass are sent" usefully characterises the partial-update contract, which implies when to use it (targeted edits rather than full replacement). But there is no explicit when-to-use/when-not guidance, no mention that customer_id must already exist, and no pointer to create_customer for new records.

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