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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds the 'public' qualifier, which is useful context, but it does not describe return format, rate semantics (e.g., borrowing vs lending rate), or any limitations. With annotations present, the added value is moderate, so a baseline 3 is appropriate.

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?

One short, front-loaded sentence that conveys the action, target, and access level with zero waste. It is appropriately sized for a low-complexity public getter.

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 read-only tool with complete schema descriptions and good annotations, the description is sufficiently complete. It explains the core purpose and scope, though it leaves the exact meaning of 'interest rates' slightly ambiguous (e.g., borrow vs. lend). Given the low complexity and no output schema, a 4 is warranted rather than 5.

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 description coverage is 100%, with both vip_level and currencies described succinctly. The description adds no additional parameter semantics beyond the schema, so the baseline 3 is correct. The tool-level description does not need to repeat what the schema already covers.

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 'Get current interest rates for specified currencies in multi-collateral loans'. The verb is specific, the resource is precise, and the qualifier 'current' distinguishes it from the sibling tool cex_mcl_get_multi_collateral_fix_rate. The word 'public' further clarifies access scope.

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 implies when to use it: when you need current rates for specific currencies. However, it does not explicitly mention alternatives such as the fixed-rate tool or the LTV tool, nor does it state when not to use it. No explicit exclusions are provided, so usage timing is inferred rather than explicit.

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