Google Health Cache Status

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the agent knows this is a safe read operation. The description adds context about the optional cache and its enablement, but doesn't disclose what the status output contains or behavior when cache is not enabled. This is acceptable given annotations and output schema.

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, front-loaded sentence that states the core purpose and then adds the key prerequisite. There is no filler or redundant information, and it is appropriately sized for the tool's simplicity.

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 status tool with one optional parameter, the combination of description, annotations, and schema provides sufficient context. The description explains what the tool shows and how to enable the cache, while the output schema (if present) would cover return details. Minor gap: it doesn't state what happens if cache is not enabled, but this is not critical.

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 only parameter, response_format, has a default and enum in the schema, but the description provides no explanation of it. With schema description coverage at 0%, the description should compensate, but it doesn't mention the parameter at all. The enum values are self-explanatory (markdown/json), but the absence of any description is a gap.

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 tool's purpose: 'Show optional local SQLite cache status.' The verb 'show' and resource 'local SQLite cache status' are specific and unambiguous. It also distinguishes itself from sibling tools, none of which focus on cache status.

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 context for when to use this tool by explaining that the cache is optional and how to enable it ('Enable with GOOGLE_HEALTH_CACHE=sqlite or GOOGLE_HEALTH_CACHE=true'). This implies the tool is relevant when cache is configured, though it doesn't explicitly state exclusions or alternatives. Sibling tools don't offer a similar function, so the guidance is adequate.

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