list_schemas

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

No annotations are provided, so the description carries the full burden. It discloses that the operation is 'Cheap' (performance characteristic) and that output respects an allowlist filter. These are genuinely useful behavioral traits beyond what schema/annotations convey.

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, zero wasted words. The description front-loads the core purpose, adds the allowlist behavioral note, flags cost ('Cheap'), and ends with actionable next-step guidance. Every sentence 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 zero-parameter listing tool with an output schema present, the description is fully complete. It declares purpose, scoping behavior, cost profile, and the follow-up tool to use. The output schema handles return-value documentation, so nothing critical 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, and schema coverage is 100% (trivially, since there are no params to document). The baseline for 0-param tools is 4, and the description appropriately adds no parameter noise while providing purpose context that helps the agent understand what the (empty) invocation will return.

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+resource ('List database schemas visible to this server') with precise scope ('honoring the configured schema allowlist'). It clearly distinguishes from siblings by pointing to list_objects as the tool for looking inside a schema, positioning list_schemas as the top-level listing operation.

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?

Explicit guidance is provided: 'Call this first to see what exists; then use list_objects to look inside a schema.' This tells the agent when to invoke it (as an entry point) and directs to the appropriate alternative (list_objects) for the next step.

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