plc_session

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

No annotations are provided, so the description must carry full transparency weight. It discloses read-only nature for 'status', logs the IDE out (destructive hint), applies deferred edits, and specifies that logout is guarded with a confirmation parameter. The only minor gap is not explicitly stating whether a successful login check or other prerequisites are needed before logout.

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 four sentences, each earning its place: first sentence sets context, second explains 'status', third explains 'logout' with side effects, fourth adds guard constraint. Front-loaded with the core mechanism. No redundant information.

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 2 parameters, no output schema, and no annotations, the description covers the essential details (actions, side effects, guard). It is complete enough for an agent to use the tool safely. Minor gap: does not describe the return format for 'status' (e.g., exact structure of { loggedIn }).

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 0%, so the description must compensate entirely. It explains the 'action' enum values and their semantics, and documents the 'confirm' parameter purpose (guard for logout). Without the description, the agent would only see an enum and a string field. The description adds significant meaning, though it could hint at expected values for 'confirm' beyond the example given.

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 specific actions ('status' for read-only login status, 'logout' for logging out), clearly identifies the resource (PLC session) and mechanism (UI Automation), and distinguishes from sibling tools by noting DTE commands are unavailable on 64-bit shell. This provides a specific verb+resource pairing with clear differentiation.

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 explicitly says when to use 'status' (read-only) vs 'logout', warns about side effects (applies source edits, never logs back in), and states a required guard ('confirm' field needed for logout). This gives clear context for tool selection and safe usage.

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