list_providers

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

The annotations already declare readOnlyHint=true, so the read-only behavior is covered, leaving the description free to add detail about the inclusion of locally installed CLIs and their subscription-based billing, which is useful. It doesn't describe the response structure or pagination, but the absence of parameters suggests a simple listing, so this is adequate.

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, no fluff. The first clearly states the primary purpose, and the second adds crucial context about the local CLIs and billing model. Every word earns its place, and it's front-loaded with the key action.

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 simple (no params, no output schema), but the description covers the essential details: what is listed, the nuance of local CLIs versus API-based, and the billing context. It could mention that the output is in a structured format, but the lack of output schema and the simplicity of the task don't demand more.

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?

With zero parameters, the description's job is to clarify what the tool returns, which it does by specifying the content: providers, default models, and the local CLI variants. Since there are no parameters, it maximizes clarity about the output, making this a strong score.

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 lists configured AI providers and their default models, and it explicitly distinguishes its scope by including locally installed agent CLIs. This differentiates it from sibling tools like brainstorm (which likely generates ideas) and add_provider (which modifies providers).

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?

It implies usage as a discovery tool for available providers, noting that some run on subscriptions rather than metered API credits, which helps in selecting providers for brainstorming. However, it doesn't explicitly state when not to use it or brand it as a read-only complement to add_provider; the context is clear but exclusions are absent.

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