list_providers

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

Annotations already mark readOnly and openWorld. The description adds behavioral context about the prompt_style field (CLIP vs natural language), a refreshed_at timestamp, and force_refresh caching behavior, which goes beyond annotation basics.

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 concise with four sentences, each providing essential information. It is front-loaded with the core purpose and structured logically: purpose, details, usage guideline, alternative resource.

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 an output schema exists (not shown but noted), the description covers behavior, caching, timestamp, prompt_style orientation, and an alternative resource access method. This is complete for a list discovery tool.

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?

Schema coverage is 100%, so baseline is 3. The description adds context about when to use force_refresh ('if providers may have changed') which is a helpful elaboration beyond the schema's explanation.

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 available providers, models, and capabilities with specific detail on prompt_style and timestamp. It distinguishes from all sibling tools which handle generation, image display, gallery, and server info.

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 explains when to use force_refresh and mentions the alternative info://providers resource, but does not explicitly state when not to use the tool or compare to siblings. However, since siblings are unrelated, usage is clear.

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