start_simulator

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

With no annotations, the description carries full disclosure burden. It reveals a non-obvious side effect (registry modification of the 'use default application (enforce security)' option) and explains why (avoiding a blocking warning dialog), plus the dependency on enforce_security.

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?

Three sentences, front-loaded with action and purpose; every sentence adds necessary information about behavior, parameter effects, or safety constraints. No filler or redundancy.

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 one optional parameter, no output schema, and no annotations, the description covers purpose, side effects, parameter semantics, and safety boundary. Nothing critical is missing for correct invocation.

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?

Although the schema only provides a title and default for enforce_security, the description explains the behavioral consequence of False vs True in concrete terms: disabling the registry option to avoid sim.exe blocking. This gives an agent enough information to choose the correct value.

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 opens with a specific action ('Start the Control Expert PLC simulator (sim.exe)') and a concrete purpose ('so plc_connect can reach it'). This clearly differentiates it from sibling operations like stop_simulator.

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?

It states when to use the tool ('so plc_connect can reach it') and an explicit restriction ('Only use on a local test machine'), giving a clear operational boundary. It does not name an alternative tool, but the complementary sibling stop_simulator is obvious from context.

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