List dialers

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds a genuinely useful data-sensitivity fact beyond the annotations: 'Credentials are never returned,' which tells the agent what the response will not leak.

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?

Two short clauses with zero filler. The primary purpose is front-loaded and the credentials caveat follows immediately where it is relevant.

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 zero-required-parameter read-only list with full schema coverage and no output schema, the definition covers purpose, downstream use, and one behavioral caveat. It is nearly complete, missing only an explicit boundary against the phone-numbers sibling.

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?

There is only one optional parameter (response_format) and schema coverage is 100%, so the schema fully documents it with enum values and a default. The description adds nothing about format selection, which is the correct baseline when the schema does the work.

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 clear verb (List) and resource (dialers), and even defines what a dialer is ('caller numbers / carrier connections') plus its role as a `dialer_id` input to calls and campaigns. It does not explicitly distinguish itself from the nearby sibling qcall_list_phone_numbers, which is the one plausible confusion point.

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?

Usage is implied by 'usable as `dialer_id` for calls and campaigns' – an agent can infer this is the lookup needed before placing a call or creating a campaign. However, there is no explicit when-to-use vs. when-not, and no routing to or away from qcall_list_phone_numbers.

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