opendss_thevenin_z1

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

Annotations already declare idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is partly covered. The description adds real method detail beyond that — the dual-fault approach, two 3-phase faults with differing R_fault, and the algebraic solve — which tells the agent how the measurement is obtained and that the circuit is perturbed. It does not state whether the applied faults are removed afterward.

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?

Front-loaded with the purpose, then method, then a clear Args/Returns block; no sentence is wasted. The Args/Returns headers are slightly boilerplate given the output schema already exists, but the content is tight.

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 precondition and method are stated, and an output schema exists so return values needn't be enumerated (though they are). What's missing is how this relates to the z0/fault siblings and whether circuit state is restored after the dual faults — minor gaps for a single-parameter analysis tool.

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?

Reported schema description coverage is 0% at the top level, so the description must compensate. It names the meaningful inputs ('bus name and two fault resistances') and explains their role in the dual-fault solve, but omits response_format and the default values of rf1/rf2, leaving the compensation partial.

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?

Names a specific verb and resource ('Extract positive-sequence Thévenin impedance (Z1) at a bus') and the 'positive-sequence' qualifier implicitly distinguishes it from the sibling opendss_thevenin_z0, which handles zero-sequence. An agent can route between the two without opening either schema.

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?

States a concrete precondition ('The circuit must be compiled first'), which tells the agent when the tool is callable. It gives no explicit exclusions or sibling routing (e.g., when to prefer z0 or a single fault tool instead), so it falls short of the top band.

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