gx3_explain_snapshot

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

With no annotations provided, the description carries the full burden and meets it. It discloses read-only file behavior, the absence of PLC connectivity, the special 'no measured value; file only' result state, and the snapshot's temporal limitation.

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 front-loaded with the core purpose, and every sentence adds a distinct piece of information. It is slightly dense, especially the sentence about rows that did evaluate, but nothing is redundant.

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 file-analysis tool with no output schema and no annotations, it covers the essential use context, read-only safety, output caveats, and temporal limitations. It is incomplete only in not characterizing the full return shape or the behavior of optional parameters.

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 43%, and the tool description does not explain the undocumented optional parameters (format, max_depth, max_devices, exclude_reset) or how they affect the result. It adds context for the required snapshot/device/root inputs, but leaves most optional parameter semantics to inference from names and defaults.

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 first sentence states a specific verb and resource: match a captured device snapshot against the enable conditions produced by the static trace, and say what the snapshot does not answer for. It also explicitly rules out trip-cause questions, so the tool's scope is unambiguous.

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 the tool reads files only, never opens a PLC connection, and that no MCP tool does. It also provides a concrete when-not-to-use example: do not use it to answer why a trip happened earlier. This is clear routing guidance.

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