Check database health

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

The description goes well beyond the readOnlyHint annotation by detailing the exact JSON response shape for both success and failure scenarios, and by specifying precise presentation rules (card layout, Markdown fallback, never mention tool name, format uptime in human units). This equips the agent to handle the tool's output correctly and addresses all behavioral nuances.

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 well-structured and front-loaded with the purpose and usage, followed by return format and formatting rules. It is somewhat lengthy but every sentence contributes necessary information, especially the output and presentation details. It could be tightened, but the organization is logical and not wasteful.

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, the description is comprehensive: it covers purpose, usage triggers, output schema (via example JSON), error handling, and rendering instructions. The presence of an output schema further reduces the need to explain return values. Nothing essential is missing for an agent to use this tool effectively.

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, db_id, is fully described in the input schema with clear semantics ('Optional named database profile configured on the server'). The tool description adds no additional meaning, but with 100% schema description coverage, the baseline of 3 is justified.

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 the tool's function: 'Check MySQL connection health and basic server status.' It uses a specific verb and resource, and the distinction from sibling tools (query, list_tables, etc.) is obvious. This is a focused health check tool with no ambiguity.

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 explicit when-to-use guidance: 'when the user asks whether the database is reachable, what version it runs, or when queries are unexpectedly failing.' It does not name alternatives or mention when not to use it, but the context is clear enough that no exclusions are needed. Since no alternative is explicitly provided, a 4 is appropriate rather than a 5.

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