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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds a valuable behavioral warning about testMode metadata not implying testnet, which is not present in the annotations. This extra context helps the agent correctly interpret the returned data.

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 redundancy, and the core purpose is front-loaded in the first sentence. The second sentence adds an essential caveat without extra verbosity. Every word earns its place.

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 zero parameters and the presence of an output schema, the description sufficiently covers the tool's purpose and an important output-interpretation caveat. It lacks no critical information for calling the tool correctly, though it could add context on typical usage scenarios, which is already reflected in the lower usage_guidelines score.

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 and schema coverage is 100%, so the baseline is 4 per the rubric. The description adds no parameter-specific meaning because there are no parameters to document. This is appropriate for a no-input read operation.

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 states a specific action and resource: 'Read currently supported assets and networks.' This clearly distinguishes it from the payment, account, and webhook sibling tools. Though the title is null, the verb+resource phrasing makes the purpose unambiguous.

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 no guidance on when to use this tool versus alternatives. The second sentence ('Do not assume metadata testMode means testnet') is a data-interpretation caveat, not a tool-selection guideline. An agent would have to infer when this list is needed (e.g., before payment creation), but that is not stated.

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