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

Annotations already indicate readOnlyHint=true and destructiveHint=false, so the agent knows this is a safe read operation. The description adds no additional behavioral context beyond the name, such as pagination, ordering, or return format. Since the output schema exists, the return structure is defined elsewhere, but the description does not mention any behavioral nuances.

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 short sentence that directly conveys the action and resource. It is front-loaded and contains no extraneous information, making it highly concise and easy to parse.

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 list operation with no parameters, the description is sufficient for an agent to invoke the tool correctly. The output schema defines the return structure, so no further detail is required. However, the description does not mention whether the list is complete or if there are any implicit filters, which is a minor gap given its simplicity.

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?

There are zero parameters, so the schema covers all parameter semantics by default (covered 100%). The description correctly states the operation without needing to elaborate on parameters. A baseline of 4 is appropriate given the absence of parameters.

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 clear verb ('List') and a specific resource ('outbound assistants'). It is unambiguous and distinct from siblings like 'list_inbound_assistants' by the explicit 'outbound' qualifier. However, it does not elaborate on what constitutes an outbound assistant, which is minor for a listing tool.

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 tool's purpose but provides no explicit guidance on when to use it over alternatives such as 'get_outbound_assistant' for a single assistant or 'list_inbound_assistants' for inbound. There are no exclusions or alternative names mentioned, leaving the agent to infer based on 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.