list_databases

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

No annotations are provided, so the description carries the burden of disclosure. It adds valuable behavioral context by specifying 'online' databases, implying that offline or unavailable databases are not included. This is a useful filter not present in the tool's name and helps set expectations.

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 with no redundancy. Every word adds meaning, efficiently conveying the tool's purpose and scope.

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?

The tool is low complexity with no parameters or output schema. The description sufficiently covers the essential context: what is listed and the filter applied. It does not describe the return format, but for a simple list operation, that is not a critical gap.

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 correctly does not attempt to explain nonexistent parameters, and the input schema is an empty object, making parameter semantics trivially clear.

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 with a specific verb ('List'), a specific resource ('databases'), and a scope ('on the SQL Server instance'). It is easily distinguishable from sibling tools that target other objects like roles, schemas, or tables.

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 context of use is clear: the agent should use this when it needs to enumerate databases on the server. No explicit exclusions are given, but the description itself implies the primary use case, which is sufficient for a simple parameterless list tool.

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