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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds the temporal qualifier 'current' and the data source, but provides no depth on response format, pagination, or how filtering/limit parameters affect behavior. No contradiction with annotations.

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?

The description is a single sentence that starts with the verb and contains zero filler. It is efficient and front-loaded, though its brevity leaves out contextual details captured by other dimensions.

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 and five optional parameters including a nested raw params object, the definition should convey what a spread response contains and how this tool relates to nearby peer_market_* tools. It does neither; return-value information is absent, and the description alone is under-specified.

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 5 params have descriptions), so the baseline is 3 even though the tool description itself adds no parameter-level meaning. The schema descriptions are minimal but present, e.g., 'Result limit' and 'Include rate entries'.

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'), a clear resource ('current market spreads'), and a source ('Peerlytics'). It is unambiguous as a read operation for spread data, though it does not explicitly differentiate itself from the many sibling peer_market_* tools such as peer_market_orderbook or peer_market_compare.

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 vs. alternatives like peer_market_orderbook, peer_market_compare, or peer_market_activity. With dozens of peer_market_* siblings, the description offers no exclusions, prerequisites, or conditions for choosing this tool.

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