prepare_funcInsert a .func directive into an LTspice schematic to define reusable expressions for simulations; specify the schematic path and function definition.
Insert a .func directive.
| Name | Required | Description | Default |
|---|---|---|---|
| definition | Yes | ||
| schematic_path | Yes | ||
| workspace_root | No | Optional per-call workspace root override. |
Changes observed during successful MCP inspections.
v0.0.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare the safety profile (readOnlyHint=false, idempotentHint=false, destructiveHint=false), so the agent knows this mutates state and is not idempotent. The description adds nothing beyond that: it does not say whether the directive is appended, replaces an existing one, or where it is placed, which matters given idempotentHint=false.
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?
It is a single front-loaded sentence with no waste, which is good. But the brevity crosses into under-specification for a required-parameter mutation tool rather than being genuinely 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?
For a 3-parameter mutation tool with no output schema and low schema coverage, the description is too thin. It omits the mechanics of insertion, expected directive syntax, and any relationship to sibling prepare_* calls, leaving real gaps an agent must guess at.
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 only 33% – workspace_root is documented, while the required 'definition' and 'schematic_path' have no descriptions. The description provides no compensating detail about the expected shape of the .func definition string, so parameter meaning remains ambiguous.
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 specific verb and resource ('Insert a .func directive'), which is more than a tautology. However, it never explains what a .func directive is or how it differs from the many sibling prepare_* tools (prepare_param, prepare_meas, prepare_step, etc.), so an agent unfamiliar with SPICE cannot confidently distinguish it.
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 when-to-use guidance, no prerequisites, and no mention of alternatives or the order in which this should be called relative to related prepare_* directives. The agent is left to infer everything from the name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.