invariance_guardrail_get

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the agent knows this is a safe read operation. The description adds the 'by ID' scoping but does not describe return behavior (e.g., what happens if not found) or any other behavioral nuances. It adds minimal context beyond annotations, so a 3 is appropriate.

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 a single, clear sentence with no fluff. The essential information—that this retrieves a guardrail by ID—is front-loaded, making it easy for an agent to quickly parse. Every word earns its place.

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 simple get-by-ID tool with no output schema, the description adequately covers the core action. It could add more context, such as confirming it returns the guardrail object or noting error behavior, but given the simplicity and the annotations covering safety, it is sufficiently complete 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?

The schema has one parameter 'id' of type string with 0% description coverage. The description mentions 'by ID', which clarifies that the 'id' parameter is the identifier to look up, adding semantic value that the schema alone does not provide. However, it does not explain the format or any constraints of the ID, so it only partially compensates for the low schema coverage.

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 uses a specific verb 'Get' and a specific resource 'guardrail', with a clear lookup key 'by ID'. It is clear what the tool does, but it does not distinguish itself from sibling tools like invariance_guardrail_list or invariance_guardrail_create. Still, for a simple get-by-ID operation, the purpose 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 gives no explicit guidance on when to use this tool versus alternatives. It does not mention that this is for retrieving a single guardrail by ID, while list or create tools exist for other scenarios. The usage is implied but not stated, so an agent must infer when to choose this over invariance_guardrail_list.

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