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

Annotations already communicate that the tool is read-only, idempotent, and non-destructive. The description adds only the purpose of the returned data, not any extra behavioral nuances, so there is no contradiction and no need for more.

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 whole description is a single sentence that puts the action first, then the object, and then the intended usage. There is no redundant phrasing or unnecessary detail.

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?

Given the tool takes no parameters and annotations fully describe its safety profile, the description is adequate for an agent to understand when and why to call it. It doesn't detail the output shape, but for a simple listing operation the phrase 'List available providers' covers the essential contract.

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 schema is trivially fully covered and no parameter documentation is required. The description correctly avoids inventing non-existent limitations.

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 uses a specific verb ('List') and a clear resource ('available providers'), and adds the purpose of configuring allow/deny/routing preferences. This distinguishes it from sibling list tools like list-models or list-presets.

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 provides clear context: call this tool when you need to configure provider allow/deny/routing preferences. It does not explicitly mention when not to use it or name alternatives, but the intended scenario is clear.

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