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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the 'live' and 'P2P' context, which is useful, but it does not disclose behavior such as orderbook depth, snapshot vs. stream semantics, aggregation, or how parameters affect results.

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 front-loaded sentence with no filler or redundancy. Every word contributes to identifying the tool's core function and live-data nature.

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 four parameters, the description is too thin to be fully actionable. It does not explain what the orderbook contains, how currency/platform/minSize interact, what the default behavior is beyond minSize=50, or what kind of response shape the agent should expect.

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%, so the baseline applies even though the tool description itself adds no parameter detail. The schema descriptions are terse ('Minimum size.', 'Fiat currency.', 'Payment platforms.'), and the description does not clarify how these map to orderbook filtering, but it is not required to compensate at this coverage level.

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 uses a specific verb ('Fetch') and identifies a distinct resource ('live P2P orderbook'), so an agent can tell this is a read-style market data tool. It is clear, though it does not explicitly differentiate itself from sibling market tools such as peer_market_spreads or peer_market_activity.

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 offers no guidance on when to choose this tool over alternatives, no exclusions, and no mention of typical use cases. An agent is left to infer that this is the tool for orderbook data without any stated selection criteria or when-not-to-use direction.

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