create_region

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

No annotations are provided, so the description must carry the full behavioral burden. It states 'Create an additional Region' which implies a mutation, but it does not disclose any side effects, permissions required, preconditions on the parent element, or error behavior. There is no mention of what happens if the parent is not a valid StateMachine or composite State. This is a significant gap for a create operation with no annotation coverage.

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, focused sentence that front-loads the action and resource. Every word contributes to the meaning: 'Create an additional Region' states the action, 'inside a StateMachine or composite State' scopes the target, and '(for concurrent/orthogonal regions)' explains the purpose. There is no fluff or redundancy, making it highly efficient.

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 the tool's simplicity (2 parameters, no nested objects) and the presence of an output schema, the description need not explain return values. However, it lacks guidance on parameter usage (e.g., what name constraints exist, whether parent_id must be a specific type), and it does not mention preconditions or error handling. With no annotations, the description leaves the agent uncertain about the required inputs and the exact behavior. It covers the core purpose but misses essential operational details.

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 by explaining the parameters. It does not explicitly map 'name' or 'parent_id' to their meanings. The phrase 'inside a StateMachine or composite State' implies parent_id is the target parent, but this is implicit and not directly tied to the parameter names. With two required parameters and zero schema documentation, the description fails to provide adequate semantic guidance.

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 specifies the action (create) and the resource (an additional Region) with explicit context of where it applies (inside a StateMachine or composite State). It distinguishes this from siblings like create_state or create_transition by naming the specific element type and its purpose (concurrent/orthogonal regions). This is a specific and unambiguous statement of what the tool does.

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 context on when to use the tool: it is for creating regions inside state machines or composite states, specifically for concurrency. It does not explicitly name alternatives or state when not to use it, but given the sibling list includes other creation tools, the context is sufficient to infer its niche. The lack of explicit exclusions prevents a 5, but it gives enough guidance for typical use.

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