is_action_registered

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

With no annotations, the description carries the behavioral disclosure burden. It states the tool is informational only, implying a read-only, non-mutating operation. It also discloses that it returns enforcement_layer/enforcement_pointer/ceremony when present. However, it does not explicitly mention side effects or error behaviors, though for a simple lookup this is less critical.

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 two sentences, front-loaded with the primary purpose. Every clause adds value: the first defines the query, the second clarifies its informational nature. No redundant or filler content.

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 the tool's low complexity and the presence of an output schema, the description is largely complete. It explains the relationship with classify_action and what data is returned. However, it does not define 'loaded rails registry' or specify edge cases, which would be helpful for full context.

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. It only uses the parameter name 'action_type' in context without explaining valid values, format, or examples. The meaning is partially implied, but the description does not add sufficient semantic value beyond the schema.

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 clearly states the tool's purpose: checking whether an action_type is registered in the rails registry. It specifies the exact resource (loaded rails registry) and the action (has an entry), and distinguishes itself from classify_action by clarifying that registration is informational only.

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 mentions classify_action as an alternative and clarifies that this tool's results do not affect classification (GATED verdict). This tells the agent when to use this tool (for informational lookup) and when not to rely on it (not for gating decisions).

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