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

No annotations are provided, so the description carries the full burden. 'Fetch' implies a read-only snapshot and the metric list tells the agent what data to expect, but it doesn't disclose output shape, freshness semantics beyond 'live', or rate limits.

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 with no filler. The verb and scope come first, followed by concrete examples of the returned metrics, making every word earn 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?

For a zero-parameter read tool, the description provides the key information: what kind of data is returned. It doesn't specify exact return formatting or units, but given the low tool complexity this is adequate.

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 takes zero parameters and the schema is empty, so the description doesn't need to document any inputs. The no-parameter baseline of 4 applies, and nothing about parameter usage is missing.

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 verb ('Fetch') and resource ('live protocol metrics') and names three concrete metric categories. It clearly reads as an overview/stats tool distinct from the transactional sibling tools, though it doesn't explicitly name a differentiating sibling.

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 gives clear context: call this to get live protocol-level metrics. It doesn't state exclusions or alternatives, but the sibling set is entirely domain/marketplace transaction operations, making the stats use case intuitively distinct.

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