db_render_er_diagram

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

No annotations are provided, so the description bears full responsibility. It reveals the tool uses Mermaid and the MCP App component, and that unsupported clients see a plain text summary plus source. However, it does not discuss side effects, read-only nature, or error handling.

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 consists of two concise sentences with no superfluous information. It front-loads the purpose and immediately adds prerequisites and behavior, making it efficient for an agent to parse.

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 no output schema, the description adequately covers the return format (rendered diagram or plain text + source) and the prerequisite. It lacks details on error handling or performance, but is otherwise complete for a diagram-generation tool.

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%, so baseline is 3. The description does not add extra meaning beyond the schema beyond implicitly mentioning 'multiple tables' for the 'tables' parameter. No parameter-specific details or examples are given.

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 the tool generates Mermaid ER diagrams for multiple tables, which is a specific verb and resource. While it does not explicitly distinguish from siblings, the purpose is clear and distinct from other db_* tools.

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 includes a clear prerequisite: must have established a connection via db_connect_test before calling. However, it does not provide guidance on when not to use this tool or suggest alternatives.

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