listConnections

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

Annotations already declare readOnlyHint, idempotentHint, and no destructiveness. The description adds valuable behavioral context beyond annotations by stating it returns purpose, engine, default schema, and local-catalog availability, and notably that it works 'without opening a database connection.'

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?

Two sentences with no filler: the first states the core capability and output, the second gives a usage condition and return details. Information is front-loaded and every clause earns its place.

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 parameterless discovery tool with rich annotations and an output schema, the description fully explains what the tool does, when to call it, what behavior to expect, and what the results contain. Nothing essential is missing.

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, so the baseline is 4. The description still adds useful semantic context by explaining that the output provides the valid name to pass as 'connection' to other tools.

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 a specific verb ('Discover') and resource ('databases served here' and valid 'connection' names), clearly differentiating this discovery tool from siblings like listSchemas or listTables. It also specifies the exact output purpose: returning a valid name to pass as the 'connection' parameter.

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 gives an explicit condition: 'Call when the target connection is not already established.' This implies the inverse case clearly, but it does not name alternative sibling tools or explicitly state when not to call beyond that condition.

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