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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the read-only nature is covered. The description adds the scope and output categories, but does not disclose response shape, record counts, freshness, or pagination behavior; with no output schema, this is a moderate gap.

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 compact sentence with a colon-separated list of output categories conveys the tool's purpose and scope without filler. Every word contributes useful information.

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 no-parameter read-only tool, the description is mostly sufficient, but it does not define how 'Epsilon' relates to the sibling scope or explain the exact output schema beyond high-level categories. Given no output schema and several overlapping siblings, a bit more detail about what is and is not included would make it complete.

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?

There are zero parameters, so no parameter documentation is needed; the schema coverage is complete at 100%. The description does not need to add parameter semantics and correctly avoids inventing any.

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 identifies the resource ('Engine-wide Epsilon stats') and specifies the exact contents: order counts by status, fill counts, and volume aggregates. It is more informative than a bare label, though it lacks an explicit verb and does not directly contrast with similarly named siblings like get_market_overview.

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 qualifier 'Engine-wide' implies this is for aggregate, cross-market statistics rather than per-order or per-token queries, but no explicit when-to-use or alternative routing is given. With many sibling tools, the absence of a direct comparison leaves some selection ambiguity.

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