database_stats

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

The annotation readOnlyHint=true already declares this as a safe read operation, so the description doesn't need to repeat that. The description adds value by listing the specific statistics returned (version, size, connections, etc.), which is useful context beyond the annotation. However, it doesn't disclose any potential side effects or performance implications, though for a read-only stats tool this is less critical.

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 lists the key statistics in a compact, front-loaded manner. Every word earns its place, and it avoids unnecessary elaboration. This is an example of efficient, well-structured description.

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, read-only annotation), the description is complete enough. It covers the main purpose and the specific data points returned. It could potentially mention that the output is a summary or snapshot, but that's a minor gap. The description is adequate for an agent to understand what to expect.

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, and the schema coverage is 100% (vacuously). The description adds meaning by explaining what the tool returns, which is the main value for a parameterless tool. Since there are no parameters to document, the description's role is to clarify the output, which it does effectively.

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 purpose: viewing database statistics including version, size, connections, current user, server address, and time. It uses a specific verb ('查看' meaning 'view') and resource ('数据库统计' meaning 'database statistics'), which distinguishes it from sibling tools like list_tables or list_sessions. However, it could be more explicit about the read-only nature, though the annotation already covers that.

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 implies usage for checking general database health and environment info, but it does not explicitly state when to use this tool versus alternatives like list_sessions or list_databases. It provides a clear context (viewing stats) but lacks explicit exclusions or alternative guidance.

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