iec61850_device_directory

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds behavioral detail about the return dictionary structure and the optional children inclusion, which is helpful. However, it does not disclose potential edge cases like empty results or errors, but given the simple read-only nature, the bar is slightly lower. No contradictions with annotations.

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 well-organized: a one-line summary, an Args section, a Returns section, and an example. Every sentence adds value—no fluff. It is appropriately sized for a tool with two parameters, and the example reinforces usage.

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 read-only listing tool with 2 optional parameters and no output schema, the description provides everything needed: purpose, parameter meanings, return format, and an invocation example. It is complete without over-explaining.

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 schema has no parameter descriptions (0% coverage), so the description carries full burden. It explains 'include_children' as 'Also browse each logical device's immediate model children' and 'endpoint' as 'Endpoint name from config (protocol 'iec61850'); omit for default.' Both parameters get clear, non-schema-derived meaning, plus a concrete example.

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 verb 'List' and a clear resource 'the IED's logical devices', immediately conveying the tool's scope. It also mentions optional behavior ('optionally their children') which distinguishes it from sibling browse/read tools. This is a strong, unambiguous purpose statement.

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?

The description provides clear context: it lists logical devices and optionally children, with endpoint from config ('omit for default'). It does not explicitly name alternative tools or when-not-to-use, but the read-only listing nature is self-evident. The instructions are actionable without being misleading.

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