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

With readOnlyHint=true already covering safety, the description adds real behavioral context: the output is a preliminary hint, the technician confirms cause and final price on site, and a consent precondition (client_accepted_disclaimer) is mandatory. That consent-and-caveat workflow is nowhere in the annotations or schema and is essential to invoking it correctly.

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?

Dense but front-loaded: the core purpose and the find_companies dependency lead, and the consent instruction follows. It is a single long passage rather than cleanly segmented sentences, so it is slightly harder to scan than it could be, but no sentence is filler.

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 5-parameter, no-output-schema tool this is complete: it names the inputs' origins, the brand vocabulary, the consent workflow, the cross-tool linkage to book_appointment, and what the response conceptually contains (probable cause plus starting price). An agent has everything needed to call it and to sequence it.

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 coverage is 100%, so the baseline is 3, but the description adds value the schema lacks: the full enumerated set of brand keys (the schema declares no enum and only says 'see the description'), and the provenance of `company` (a find_companies result). `code`, `lang`, and the consent flag are already well documented in the schema.

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+resource: returns a probable cause (breakdown type) and starting price given an AC brand and display error code. It also explicitly frames what it is NOT ('It is not a diagnosis'), which separates it from an authoritative diagnosis in a way an agent can act on.

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?

Gives clear preconditions: the company must come from find_companies, the client must be told it is an automatic hint and must agree before the call, and the flag must be reused in book_appointment. It does not name any sibling to use instead nor any exclusion case beyond 'not a diagnosis', so it stops short of the top of the scale.

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