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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, and the description reinforces these with 'makes no network request and its answer never changes between calls' — a useful, unambiguous statement for a reference tool. It adds framing beyond the annotations, though it largely restates the idempotent/openWorld hints rather than revealing new behavioral traits.

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?

Two sentences, front-loaded with the action and the enumerated outcome list, followed by one short clarifying sentence about its static nature. Every clause earns its place with no filler.

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?

With no parameters and no output schema, the description carries the full burden and does so: it lists the six possible outcomes and states that meanings and next moves are included, so an agent knows exactly what the return contains. Nothing needed to call or interpret it is missing.

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 takes zero parameters, so the baseline is 4; there is no argument syntax an agent could get wrong. The description correctly spends no words on inputs and instead documents the conceptual content of the response.

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?

States a specific verb and resource ('Returns the six outcomes this server can report') and enumerates the exact outcome values, so an agent knows precisely what it will get back. The closing line ('A static reference') distinguishes it from the sibling check/drift tools that perform live network probes.

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?

Positions the tool for 'an agent choosing a server from the registry' and notes it supplies 'the usual next move for each' outcome, which is clear context for interpreting results. It stops short of explicitly saying to call this instead of or alongside mcp_liveness_check, so no hard exclusions or sequencing are given.

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