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

Annotations mark this as a non-readonly, open-world, non-idempotent write; the description adds real value on top by disclosing callback timing ('within the hour during business hours'), cost ('Free to the homeowner'), the consent requirement, and that a reference is returned. It does not warn that repeat submissions may create duplicate requests despite idempotentHint=false.

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?

Front-loaded with the core action and scoped tightly to four short sentences. The parenthetical '(a vetted local pro calls back within the hour during business hours)' redundantly restates the preceding clause, which is the only real waste.

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?

With no output schema, the description usefully states 'Returns a reference and what happens next', and covers consent, cost, callback timing, and ZIP pre-validation. Only the duplicate-submission behavior implied by non-idempotency is left unaddressed.

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%, so the schema already documents all seven parameters with constraints and examples. The description adds only indirect color ('a real person', 'their consent') that maps loosely to name/phone semantics, so baseline 3 is correct.

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 ('Book AC repair'), the geographic scope (El Paso area), and the qualifying condition (a real person who asked for it, with consent). It is immediately distinguishable from check_service_area and get_service_info, which it explicitly names.

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?

Names the prerequisite alternative explicitly: 'Check the ZIP with check_service_area first if unsure.' This gives a clear routing rule to a sibling tool, though it offers no explicit when-not-to-use condition or guidance on get_service_info.

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