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

Annotations only declare readOnly and openWorld; the description adds real operational context — advisory-only with no order placement, roughly seconds of latency, one coin per invocation, and per-call payment of 0.28 USDC via x402 at a named endpoint. That is meaningful disclosure beyond structured fields, though it omits failure modes (unsupported coins, stale data).

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 first sentence is excellent and front-loaded, but more than half the text is promotional: a 10% fee earmark to a token contract address, ERC-8004 agent ID, two verification URLs, and payout wallet address. Only the x402 payment line earns its place operationally; the rest crowds out the signal.

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 does the necessary work by enumerating the returned fields and caution/funding flags, and it covers inputs, latency, and cost. It is essentially complete for a one-parameter advisory tool, lacking only edge-case behavior.

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% and the single parameter is already documented with examples, so the bar is low. The description restates the input as {"coin":"BTC"} and clarifies "no discretionary or news input," confirming coin is the only lever — marginal but consistent value.

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 opening sentence names a specific verb and artifact — a rules-based Hyperliquid perp setup — and enumerates exactly what it returns (side, entry zone, stop-loss, TP1/TP2, R:R) plus the inputs it derives from (1h/4h trend, ATR, swing structure, funding). This clearly separates it from siblings such as hl_funding_snapshot or token_technical_analysis.

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?

"One coin per job, no discretionary or news input; advisory only, no orders placed" sets the scope and rules out misuse, and "Seconds" signals it is the fast path. However, it never names an alternative or states when an agent should prefer trade_strategy_consult or token_technical_analysis instead, so sibling routing is left to inference.

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