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

No annotations are present, so the description must carry the burden. It discloses the output fields (live XAU spot price, custody info, MiCA relevance) and implies a read-only operation. However, it does not discuss potential delays, caching behavior, or how empty results are handled, which would be useful for transparency.

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 a single, front-loaded sentence that states the core purpose first, then adds relevant details. No redundant words or filler, making it highly concise and well-structured.

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 list tool with no output schema, the description covers the essential content: token list, live price, custody info, and MiCA relevance. It could mention the return format or sorting, but overall it is sufficiently complete for its low 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?

The tool has zero parameters, so the baseline is 4. The description reinforces that no input is needed by stating it returns 'All' tokens, and the schema is trivially complete. No further parameter explanation is necessary.

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 specifies the resource (gold-backed RWA tokens), the scope (all from the registry), and gives concrete examples (PAXG, XAUT, XAUM). This clearly distinguishes it from sibling tools like reserve_silver or reserve_metals, making the intent immediately obvious.

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?

Usage is implied by the resource type: this tool is for retrieving gold-backed token data. It does not explicitly state when to use this vs alternatives, nor does it mention any exclusions. This meets the 'implied usage' level but lacks direct guidance.

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