Order Book Levels (L4)

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

Annotations cover readOnly/idempotent/destructive, but the description adds substantial behavioral context beyond them: 60 s refresh cadence, latest-only with no history, the meaning of as_of_height at the L1 block, the caution to check age_s before citing, and the Pro-tier requirement. This is rich disclosure layered on top of 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?

Dense but front-loaded: the answer to 'what does this provide' leads, followed by the example, then caveats. Every sentence carries information, though the em-dash-heavy prose is slightly heavy for the payload.

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 compensates by naming the returned fields (total size, order count, DISTINCT WALLET count, oldest-order age, as_of_height) and the freshness constraint. An agent has everything needed to call and interpret it correctly.

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 coverage is 100% so the schema already documents coin, depth, and useToonFormat, giving a baseline of 3. The description adds value by showing depth=5 in a worked example and pointing to bids[2].wallets, tying the parameter to the returned structure rather than merely restating it.

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?

States a concrete verb+resource (top price levels per side, best-first) and explicitly contrasts with the aggregated L2 view via 'market_orderbook remains the aggregated L2 view; this is the L4 one'. An agent can distinguish this from siblings without opening the schema.

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?

Explicitly names the alternative (market_orderbook) and the condition selecting this tool, plus a concrete use case ('is SOL's 3rd bid level real depth or one wallet?'). The L2-vs-L4 routing is spelled out.

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