Create agent

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

Annotations already indicate this is not destructive (destructiveHint: false). The description adds that it creates an agent with its own resources and returns an agent id, and is subject to plan limits. It does not disclose further behavioral traits like potential costs or side effects beyond plan limits, but provides adequate context given the annotations. No contradiction with annotations.

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 three sentences long, front-loaded with the core purpose. Each sentence provides essential information: creation, what an agent is, return value, and constraints. No redundant or unnecessary text. Highly concise and well-structured.

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?

Given no output schema, the description explains the return value (agent id). It covers creation specifics (disk, tools, memory) and constraints (plan limits, model tier). It does not mention potential asynchronous behavior or creation time, but for a simple creation tool, the context is largely complete and useful for an AI agent.

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%, and the description does not add new meaning beyond what is already in the schema. The model parameter description in the schema covers the default behavior and paid plan requirement. Thus, the description adds no additional value for parameter semantics, meeting baseline expectations.

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 'Create a new agent' and explains what an agent is (cloud computer with disk, tools, memory). It distinguishes from sibling tools like delete_agent and get_agent by the creation action, but it does not explicitly differentiate from similar tools like schedule_run or invoke_agent. The purpose is clear, but lacks sibling differentiation.

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 mentions account plan limits and model tier constraints, which provide some context on when to use (under plan limits). However, it does not explicitly state when to use this tool versus alternatives like invoke_agent or schedule_run. There is no guidance on prerequisites or when not to use it, making it moderately clear but incomplete.

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