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

Annotations already convey readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the 'recent' time scope and 'authenticated business' boundary, but it does not disclose ordering, time-window semantics, or pagination behavior beyond what the schema already provides.

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 description is a single front-loaded sentence with no filler or redundant restatement of the title. It communicates the core action and scope efficiently, earning its place.

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 simple list tool with fully documented parameters and an output schema, the description is mostly sufficient. However, it leaves 'recent' undefined and does not help the agent decide between this tool and sibling call-related tools, which creates a meaningful contextual gap.

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%, with every parameter documented (limit, offset, status, agent_id). The tool description adds no additional meaning to these parameters, so the baseline of 3 is appropriate.

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?

The description uses a clear verb and resource: 'List recent calls for the authenticated business'. It distinguishes the tool from list_sms_messages, list_voicemails, and list_conversations by the resource type, but it does not define 'recent' or explicitly differentiate it from call-status or recording 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?

There is no guidance about when to use this tool versus related siblings like check_call_status, get_call_recording, or get_transcript. The description provides no alternatives, exclusions, or preconditions, leaving the agent to infer the appropriate context from the tool name alone.

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