Set a DUT variable value in an IC-CAP project. Provide the full variable path and a scalar string or JSON array string to update the device parameter.
Set a DUT variable value. Pass scalar values as strings and arrays as JSON array strings such as '["a","b"]'.
| Name | Required | Description | Default |
|---|---|---|---|
| value | Yes | ||
| var_path | Yes | Full path |
Changes observed during successful MCP inspections.
v0.2.2Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden. It discloses only the value serialization format and does not mention side effects such as overwriting existing values, error behavior, or what the tool returns.
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 with no filler. Every phrase contributes either the core action or a necessary input-format detail.
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 simple two-parameter setter, the description covers the main action and value encoding, but the absence of annotations and output schema leaves behavioral expectations and usage context under-specified. An agent would need to infer side effects and when this tool is appropriate relative to sibling tools.
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?
The description adds useful meaning for the value parameter by explaining scalar values must be strings and arrays must be JSON array strings. However, var_path is only described in the schema as 'Full path', and with 50% schema coverage the description does not fully compensate for the missing var_path semantics.
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 'Set a DUT variable value' uses a specific verb and resource, clearly indicating this tool modifies an existing DUT variable. It is distinguishable from related get/create tools, though it does not explicitly name a sibling or contrast its scope.
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?
There is no guidance on when to use dvar_set versus alternatives like dvar_create or dvar_get, and no mention of prerequisites or exclusion conditions. The only guidance is about value formatting, which is a parameter detail rather than usage context.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.