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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is covered. The description adds the 'live' aspect and enumerates categories, which is useful but not deep behavioral context. It doesn't describe pagination, response shape, or any rate limiting, but the annotations cover the most critical trait (read-only).

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?

A single, front-loaded sentence that conveys the core action and scope. It lists all asset categories compactly with examples, contains zero fluff, and is appropriately concise for its purpose.

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?

With no output schema, the description should explain the return format (e.g., a list of instruments with prices) and any pagination behavior. It does not. The existence of limit/offset in the schema implies pagination, but the description leaves the response shape to the agent's imagination. Given the tool is a listing endpoint, this is a notable gap.

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%—all three parameters (limit, offset, category) have detailed descriptions including examples. The description does not add any parameter-specific meaning beyond what the schema provides; it merely restates the categories. Thus it meets the baseline of 3 without adding extra value.

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 fetches live prices across multiple asset classes (crypto, stocks, commodities, futures, currencies) with examples. It specifies the verb 'Get' and the resource 'live prices', making the purpose unambiguous. However, it does not explicitly distinguish itself from sibling tools like markets_quote or markets_history, which could be seen as overlapping.

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?

There is no guidance on when to use this tool versus alternatives. The description does not mention markets_quote (for a specific symbol's quote) or markets_history (for historical data), nor does it state scenarios like 'use this to browse all available instruments'. The when-to-use context is entirely absent.

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