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

Annotations already declare the safety profile (readOnlyHint=false, destructiveHint=true, idempotentHint=false), and the description usefully adds the master-API-key auth requirement and a per-request price. However, it does not disclose side effects, retry/non-idempotency implications, or how duplicate calls are handled.

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 purpose and auth prerequisite are front-loaded in a single tight sentence, and the pricing note is clearly delimited boilerplate. Slightly padded by the pricing comment block but no wasted prose in the functional content.

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 an output schema present, return values need not be described, and annotations cover mutation risk. Still, for a 12-parameter mutation tool with zero required fields, the description gives no indication of which fields matter, minimum viable payload, or batching behaviour.

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% across all 12 parameters, so the schema already carries the field semantics. The description adds no parameter-level meaning (e.g., the relationship between logged, status, and the ID fields), so the baseline 3 applies.

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 plus resource: 'Create call records.' An agent can distinguish this from get_apollo_phone_calls_search (read) and put_apollo_phone_calls_id (update) by the naming pattern, but the description never explicitly differentiates itself from those siblings.

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?

The only guidance is an authentication prerequisite ('Requires a master API key'). There is no statement of when to use this tool versus the search/get/update phone-call siblings, nor any when-not condition.

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