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

Goes well beyond the readOnly/idempotent annotations: it discloses per-part source and as-of timestamps, that missing parts are null with a reason, that a total build failure returns 503 and is never billed, and the exact price and payment rails (0.02 USDC via x402 on Solana/Base/Polygon/Arbitrum/Arc). These are exactly the cost, failure, and data-provenance facts an agent needs before invoking.

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 opening content inventory is long but earns its length by letting an agent judge coverage at a glance, and the operational facts (nulls, 503, billing) are packed into short trailing sentences. Slight density cost, but front-loaded and waste-free.

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 an output schema present, return shape need not be explained; the description still covers the non-schema essentials — data provenance, null/missing semantics, failure mode, and cost. Nothing an agent needs to decide and pay for the call is missing.

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% and the single symbol parameter's allowed values are already documented in the schema; the description repeats 'BTC, ETH, SOL or HYPE' without adding format, casing, or default-resolution detail beyond what the schema states. Baseline 3 applies when the schema carries the parameter semantics.

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 specific resource (composite market state) and enumerates exactly which series it bundles: spot, perp basis vs Hyperliquid oracle, realized vol, funding z-score, OI, whale net-long share, liquidations, Fear and Greed, macro calendar, flags. An agent can distinguish it from narrower siblings like get_basis, get_fear_greed, get_open_interest, or get_market_snapshot 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?

The phrase 'in one call' implies this is the aggregation shortcut versus calling the many single-metric siblings, and the symbol list constrains the universe. However, no sibling is named explicitly and there is no when-not guidance (e.g. when a single cheap metric is preferable to the 0.02 USDC bundle).

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