list_received_emails

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

With no annotations, the description carries the behavioral disclosure burden. It mentions cursor pagination, a useful behavioral trait, and 'list' implies a read-only operation. However, it does not describe the return format, pagination token semantics, or any error/rate-limit behavior. It adds some value but leaves significant gaps.

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, dense sentence that front-loads the primary purpose, includes the resource type, pagination mechanism, and endpoint. There is zero redundancy, and every word earns 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 tool with no annotations, no output schema, and zero parameter descriptions, the description is too sparse. It fails to explain the semantics of the three pagination parameters or what the response contains. An agent would need to guess API conventions, making this incomplete for correct invocation.

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 0%, so the description must compensate. It introduces cursor pagination, which hints that 'after' and 'before' are pagination tokens, adding meaning beyond the bare schema. But it does not explicitly define each parameter's role, leaving ambiguity about cursor direction and ordering. It provides partial value but not complete clarity.

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 clearly states the tool lists inbound (received) emails using a specific verb and resource, explicitly scoping to received messages. It also includes the endpoint (GET /emails/receiving), which distinguishes it from siblings like list_emails and get_received_email 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 implies the use case: when you need to list received emails. However, it does not explicitly state when to use this instead of alternatives such as list_emails or get_received_email, nor does it mention any exclusions. The context is clear but not explicit about alternatives.

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