Create a Combined Fragment in an Interaction with specified operator (alt, opt, etc.) and name.
Create a CombinedFragment in an Interaction. operator: alt | opt | loop | break | par | seq | strict | neg.
| Name | Required | Description | Default |
|---|---|---|---|
| name | Yes | ||
| operator | Yes | ||
| interaction_id | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of behavioral disclosure. It only states the creation action, but does not mention side effects, required permissions, reversibility, or what happens if the Interaction does not exist. The presence of an output schema partially covers return values, but the mutation behavior is underexplained.
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, front-loaded sentence that immediately states the action and includes the key constraint (operator values). It is concise with no wasted words, achieving high efficiency.
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?
The tool is relatively simple (3 required parameters), but the description lacks context on the meaning of interaction_id and name, and does not mention any prerequisites (e.g., the Interaction must exist). The output schema covers return values, but the description is not fully self-contained for an agent to call it correctly without additional inference.
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 adds value by listing valid operator values ('alt | opt | loop | break | par | seq | strict | neg'), which is not in the schema. However, it provides no meaning for interaction_id or name, leaving those parameters underspecified. Partial compensation, but incomplete.
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 action ('Create a CombinedFragment') and the context ('in an Interaction'), which distinguishes it from other create_* tools for different UML elements. It also lists allowed operator values, reinforcing the specific purpose.
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 does not explicitly state when to use this tool versus alternatives. It implies usage for creating a CombinedFragment, but lacks guidance on prerequisites (e.g., an existing Interaction) or when other create tools would be more appropriate. Given the large sibling set, explicit routing would improve the score.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.