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

Beyond the readOnlyHint annotation, the description discloses meaningful runtime behavior: the tool falls back from Hyperliquid to Bybit, the response names which venue answered, and positive imbalance means more bid depth. This gives the agent expectations that annotations alone do not capture.

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?

Two compact sentences convey the metric set, polarity convention, venue fallback, and response naming behavior. The most important scoping information is front-loaded, and every sentence adds new information.

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?

Given a single required parameter, a high-coverage schema, an output schema, and a read-only annotation, the description covers the needed behavioral details: what the snapshot contains, how imbalance is signed, and which venue will respond. Nothing essential is missing for selecting and calling this tool.

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?

The sole parameter symbol is fully documented in the schema with an example, and the description reinforces that it is a coin symbol for a perpetuals contract. This meets the baseline of schema-driven coverage, but the description adds little extra semantic depth beyond 'one coin's perpetuals.'

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 names a concrete resource — an order-book snapshot for one coin's perpetuals — and specifies what is included: best bid/ask, spread in bps, top-of-book depth, and imbalance. It also distinguishes itself by noting the single-venue Hyperliquid/Bybit fallback behavior, which sets it apart from broader market or multi-venue tools.

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 makes the use case clear: retrieving current order-book liquidity and depth imbalance for a single coin's perpetuals. It does not explicitly name siblings or say when not to use it, but the 'single-venue by nature' warning helps an agent avoid treating it as a multi-venue comparison tool.

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