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

With no annotations provided, the description carries the full burden. It discloses that no API key is required and identifies the HTTP endpoint, which is useful behavioral context. However, it does not describe the response format, what constitutes a healthy status, or any side effects (expected to be none).

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 short sentences, zero fluff. The key behavioral insight (no API key required) is front-loaded in the second sentence, and the endpoint mapping adds useful precision. Every sentence earns its place.

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 simple health-check tool with a single optional parameter and an output schema present, the description is mostly sufficient. It correctly signals that no auth setup is needed and maps to a known endpoint. It could mention the output schema's meaning or indicate that this tool is useful for liveness checks, but the current state is adequate for an agent to call 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%: the only parameter, api_key, is documented in the schema with its default and meaning. The description adds that no API key is required, which clarifies the optional nature of the parameter but does not add deeper semantic meaning beyond the schema.

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 ('Check') and resource ('API health status'), clearly indicating the tool's purpose. It does not explicitly differentiate from siblings like get_version or get_dataset_status, but the health-check focus is distinct enough given the tool name.

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 notes that it maps to GET /health and requires no API key, giving context that this is a lightweight, unauthenticated health check. It does not explicitly state when to use this tool versus alternatives like get_version or get_dataset_status, so the when-to-use guidance is implied rather than explicit.

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