Check whether a specific instrument variable or option field exists at a given project path. Returns a boolean result to confirm presence before further operations.
Check if an instrument option field exists.
| Name | Required | Description | Default |
|---|---|---|---|
| field_name | Yes | ||
| input_output_path | Yes |
Changes observed during successful MCP inspections.
v0.2.2Does 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. 'Check if...exists' implies a boolean result and a read-only operation, but it does not state the return type, behavior when the field is missing, handling of invalid paths, or whether any errors are raised.
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 concise sentence with no filler. It front-loads the core purpose, though the phrase 'instrument option field' is slightly vague and could have been clearer.
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 there is no output schema, no annotations, and no parameter documentation, the description is too thin for an agent to confidently call this tool. The agent is left without knowledge of the return format or the meaning of input_output_path, making the tool incomplete in context.
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%, and the description provides no explanation of the two required parameters, input_output_path and field_name. While 'instrument option field' hints at field_name, input_output_path is completely unexplained, leaving the agent to guess what path structure is expected.
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 ('Check') and resource ('instrument option field'), so an agent knows this is an existence-check tool. It is not tautological and is distinct enough in intent from instrvar_get and instrvar_set, though it does not explicitly name those alternatives.
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?
No guidance is given about when to use this tool versus the many related existence-check tools such as object_exist, mpar_exists, dpar_exists, or tablevar_exists. The description does not explain whether this should be called before instrvar_get/instrvar_set or what conditions warrant it.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.