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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only describes the output content and does not mention filtering behavior, ordering, pagination, default limit, read-only characteristics, or what happens when no matching calls exist.

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 compact sentence with no fluff and the main noun phrase is front-loaded. It loses a point only because the brevity leaves out important behavioral and parameter context.

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 call listing tool with four parameters, no annotations, and no output schema, the description is incomplete. It communicates what data comes back but not how to invoke filtering options, what each parameter means, or any pagination behavior.

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 only 25%, with only 'after' documented. The description does not explain 'chat', 'before', or 'limit' at all, and the mention of caller and time refers to output fields rather than input parameters. This fails to compensate for the sparse 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?

The description identifies the resource as 'call events' and lists the key output fields: who called, when, and answered/missed status. The title supplies the 'List' verb徙, and the subject matter distinguishes it from message- and chat-focused siblings, though an explicit 'Lists call events' phrasing would have been stronger.

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 on when to use this tool versus alternatives such as list_messages or list_chats. It does not explain whether the chat/before/after parameters are filters, how the default limit applies, or any prerequisites for getting useful results.

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