register_instance

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

Discloses testing with SELECT 1 and replacement of existing connections; no annotations provided, so description carries burden well, though omits potential side effects or concurrency 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?

Well-structured with Args section but slightly verbose; could be trimmed while retaining clarity.

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?

Covers purpose, behavior, and return value; output schema exists, so description is adequate; no major gaps identified.

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?

With 0% schema coverage, description thoroughly explains each parameter's meaning, including defaults for charset and database, adding significant value beyond the 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?

Clearly states it registers a MySQL-compatible database connection at runtime, distinguishing it from siblings like execute_sql and list_instances.

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?

Explains connection testing and replacement behavior but lacks explicit guidance on when to use vs alternatives, e.g., when a connection object is needed.

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