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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explicitly states that the operation is read-only and has no execution or payment authority, which is valuable safety information. It does not mention authentication, rate limits, or failure behavior, but for a zero-parameter polling tool this is reasonably 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 well-structured sentence that front-loads the action and resource, lists the key returned fields, and adds a clear read-only safety note. Every clause adds information, and there is 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?

For a tool with zero parameters and no output schema, the description covers everything an agent needs: what it does, what data it returns, and its side-effect profile. The tool is simple enough that this description is complete for selection and 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?

There are no parameters, so the baseline is 4. The description correctly focuses on what the heartbeat returns rather than parameter details, which are unnecessary here. No additional parameter semantics are needed.

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 ('Poll') and names the exact resource ('MUJ428 Trust Heartbeat'), then enumerates the specific data it returns: policy epoch, accepted receipt version, revocation state, resolver endpoints, and poll interval. This clearly distinguishes it from sibling tools like get_capabilities or get_service_catalog, which target different resources.

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 implies the tool should be used to retrieve current trust heartbeat state, and the read-only note helps set expectations. However, it does not explicitly say when to choose this tool over alternatives or when not to use it, leaving usage guidance mostly implicit.

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