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 valuable behavioral context: it is a read that does not edit the enum, it makes no LLM call, and it reports counts from recent enrichment records. This goes beyond the annotations by explaining the operation's non-mutating nature and data source.

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 compact and front-loaded: the core action and scope appear in the first sentence, followed by usage guidance and exclusions. Every sentence adds value, and the reference to enricher://docs/schema-reference is a useful pointer without bloating the text.

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 single-parameter read tool with a full output schema and annotations covering safety, the description is complete. It explains the purpose, the open/closed enum distinction, when to use it, and what it does not do. An agent has everything needed to invoke it correctly.

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 100%, so the schema already documents the single parameter (schema_id as UUID of the saved schema). The description does not add parameter-specific details beyond what the schema provides, but with full coverage the baseline of 3 is appropriate.

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 a specific verb ('List') and resource ('observed values outside each open enum's current vocabulary'), and distinguishes it from related tools by noting it is a read that does not edit the enum. It also clarifies the distinction between open and closed enums, which helps an agent understand the tool's exact scope.

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 this tool: to propose admitted members or rejected_values, or to close a vocabulary only when exhaustive. It also names alternatives (get_schema_part for reading named enums, update_schema for changing them) and states that this tool does not edit the enum, providing clear when-not-to-use guidance.

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