List image provider capabilities

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds value by detailing the exact contents of the report (providers, default provider/models, known options, output directory fallback, directory restrictions), which goes beyond the annotations and clarifies expected behavior.

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, two sentences, with the core purpose front-loaded and a usage hint appended. Every word earns its place, with no fluff or repetition of structured annotations.

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 simple, no-parameter listing tool, the description fully explains what the tool reports and when to use it. No output schema exists, but the description compensates by listing the kinds of information returned. Overall, it is complete for its complexity.

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?

There are no parameters (schema is an empty object), so the description does not need to explain parameter meanings. The baseline for 0 params is 4, and the description appropriately avoids adding irrelevant parameter details.

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's function as reporting image provider capabilities, enumerating specific details (providers, defaults, model options, output directory fallback, restrictions). It distinguishes itself from sibling tools (generate_image, edit_image) by being a read-only inspection tool.

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?

Provides explicit guidance on when to use the tool: 'Call this first if unsure what is available or why a call failed.' This is helpful, though it does not explicitly mention alternatives or when not to use it, relying on sibling names for differentiation.

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