List configured databases

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

Beyond the readOnly/idempotent annotations, the description discloses that it reads only server configuration and never connects to SQL Server, plus the exact failure shape when nothing is configured (ok: false with file to create, search locations, and an example). These operational details are not available in the annotations and materially affect how an agent handles the result.

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?

Three sentences, each load-bearing: what is returned, why to call it first, and what the failure path looks like. The most important guidance ('Call it first') is front-loaded after the purpose statement.

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?

With no output schema, the description fully describes the returned payload (names plus row limit and timeout per entry) and the error payload shape. Nothing an agent needs to call this zero-parameter tool correctly 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?

Zero parameters, so the baseline of 4 applies. The description does explain the downstream convention that the returned names are consumed as a 'database' argument by other tools, which adds a little semantic value, but there is no parameter syntax to clarify.

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?

States a specific verb and resource ('Lists the logical database names this server is configured to reach') and further narrows scope by naming what each entry contains (row limit, command timeout). An agent can distinguish it from siblings like get_database_overview or list_schemas immediately.

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?

Explicitly instructs 'Call it first' and explains why: every other tool, starting with get_database_overview, requires one of these names as its 'database' argument. The ordering dependency and the downstream consumer are both named, leaving no inference to the agent.

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