Builder Fills

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

Beyond the readOnly/idempotent annotations, the description discloses important limitations: trigger-order fills are not yet attributed, the feed undercounts versus ledger revenue, the lookback is clamped to 90d, and untracked order ids are null. It also points to dataNotes for further context. This is strong behavioral disclosure.

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 dense but well-structured, leading with the core purpose, then filters, return fields, known limitations, use cases, and access requirements. Every sentence delivers new information without redundancy.

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 enumerating the returned fields (time, wallet, coin, marketType, side, price, size, USD volume, realized PnL, builderFeeUsd, tid, order id). It also covers caveats, authentication requirements, and filtering options, making the tool fully callable without additional context.

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 baseline is 3, but the description adds useful meaning by interpreting the since parameter ('30m', '6h', '7d', clamped to 90d) and explaining coin filter variants (BTC, xyz:GOLD, @123 spot, #10010 HIP-4). It enriches rather than merely repeating the schema.

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 and resource: returns individual fills attributed to a builder address within a lookback window. It clearly distinguishes itself from sibling builder tools by focusing on fills, their fields, and the builder attribution model.

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 concrete use cases ('show me the flow going through frontend X right now' or auditing one wallet's activity via a builder) and notes the Pro tier requirement. It does not explicitly name alternatives or exclusions, but the context is clear enough for an agent to select this tool appropriately.

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