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

With no annotations provided, the description carries the full burden. It explicitly states 'Read-only', 'advances nothing', and 'safe to call at any rate', disclosing the absence of side effects and mutation. It also enumerates exactly what information is returned, making the behavior fully transparent.

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, dense sentence that front-loads the read-only nature. It lists specific bucket names and subjects, which are necessary for agent understanding. While it is longer than a simple sentence, every element adds value; it could be slightly more structured but is appropriately concise for the amount of information conveyed.

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 read-only status tool with no parameters and no output schema, the description fully explains what it returns and how it is used. It covers the resources, subjects, and the relationship to sibling tools. There is no missing information an agent would need 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?

The tool has zero parameters, so the description does not need to explain parameter semantics. Schema coverage is trivially 100% with an empty schema. The description adds no parameter-specific details, but none are needed; baseline for zero params is 4.

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 it is a read-only status tool that exposes the Universal Manifold Controller tip, KV buckets, Long Play domains, NATS subjects, and the MCP tool surface. It names specific resources and explicitly ties its purpose to discovering what umc_direct and umc_resume act on, distinguishing it from those siblings.

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 'Use it to discover what umc_direct and umc_resume will act on,' giving a clear when-to-use. It also notes 'takes no arguments, advances nothing, and is safe to call at any rate,' implying it can be used freely. It does not explicitly mention when not to use it or list alternatives beyond the two siblings, but the guidance is clear enough.

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