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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states what the tool returns (status and library versions) but does not explicitly mention that it is a read-only/non-destructive operation, nor does it describe any side effects, authentication needs, or rate limits. This is a significant gap for a tool with no annotation support.

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 concise sentence that immediately communicates the tool's purpose. It avoids unnecessary detail and is well-structured, earning every word it uses.

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 simplicity (no parameters, no output schema, no annotations), the description is minimally adequate. It tells the agent what information is available (server status and library versions) but does not elaborate on the format or meaning of the status, nor does it specify whether the result is a string, object, or list. More detail would improve completeness, but the description is not entirely insufficient for a health check.

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 there are no parameter semantics to clarify. The schema is an empty object with 100% coverage, and the description correctly implies no inputs are needed. A baseline of 4 is appropriate since there is no parameter documentation burden.

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 that the tool reports server status and available library versions, which is a specific health check function distinct from the invoice processing siblings. However, it lacks a verb phrase like 'check' or 'return', instead using a noun phrase, which makes it slightly less directive.

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 provides no guidance on when to use this tool versus alternatives. It does not mention prerequisites, typical use cases, or scenarios where another tool should be used. The context is implied only by the name 'health_check' and the system context, but no explicit instructions are given.

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