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

The description adds meaningful behavioral context beyond the annotations: it discloses that list endpoints are paginated, caps results at 30 per page, and tells the caller to inspect current_page, last_page, and total to determine whether more pages exist. This is useful runtime behavior that annotations alone do not convey.

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 compact and front-loaded with the main purpose before pagination details. The opening line repeats the tool title, which is mildly redundant, but every other sentence earns its place by giving operationally useful pagination instructions.

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 three-parameter read-only list tool with an output schema and strong annotations, the description is complete. It tells the agent what the tool does, how to paginate, and how to recognize whether more pages exist, so no critical information needed to call it correctly is missing.

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 coverage is 100%, so the schema already documents id, page, and limit. The description reinforces the pagination purpose of page and limit and notes the 30-record cap, but it does not add meaning beyond what the schema properties already state.

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 states a specific verb and resource: 'Retrieve message history for one customer.' The explicit 'for one customer' scope distinguishes it from siblings like listMessages, which presumably returns all messages, without needing to open any schema.

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 description provides clear pagination guidance: use page and limit, at most 30 records per page, and check the pagination object to decide whether to keep fetching. However, it does not explicitly state when to prefer this over listMessages or other listing tools, relying only on the implied per-customer scope.

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