health_check

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

Since no annotations are provided, the description carries the full burden. It discloses that a failure indicates credentials are invalid and that all other tools will also fail. This is critical behavioral context beyond a simple 'check'.

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?

Three sentences with no wasted words. The main point is front-loaded: 'Verify credentials work.' Then gives usage guidelines and an example. Every sentence adds value.

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, the description is complete. It explains purpose, usage, expected output, and consequence of failure. Output schema is present, so no need to describe return format.

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 zero parameters, so the baseline is 4. The description adds meaning by explaining that the tool requires no inputs and simply returns a status. This provides context beyond the empty 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?

Description clearly states the purpose: verifying credentials work. The verb 'verify' and resource 'credentials' are specific. It distinguishes health_check from sibling tools like create_vehicle or list_inventory, which perform other actions.

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?

Explicit guidance on when to use: 'starting a session or troubleshooting auth errors.' Also provides an example call and expected output, plus what to do if it fails. No mention of when not to use, but the affirmative guidance is sufficient.

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