hl_market_data

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

With no annotations, the description carries the full burden and does disclose two meaningful traits: read-only nature and no auth/signing required. However, it says nothing about rate limits, pagination, defaults, or the shape of the returned data, so behavioral coverage is partial.

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?

A single front-loaded sentence lists the reads, and the trailing clause captures the read-only constraint. Every phrase earns its place with no filler.

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?

For a read-only, no-output-schema tool the description covers the essential kinds and the safety profile, which is enough to invoke it correctly. Minor gaps remain around return format and per-kind parameter defaults, but these are lower-stakes here.

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%, so every parameter (coin, kind, startTime, endTime, interval) is already documented in the schema. The description's data-kind enumeration loosely maps to the `kind` enum but adds no syntax or format detail beyond what the schema provides — the baseline 3 for high coverage.

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 verb ("Read") plus resource ("Hyperliquid market data") and enumerates the concrete reads available: mid prices, order book, candles, perp metadata. This clearly distinguishes it from the account/trading siblings (hl_place_order, hl_account, hl_transfer), which an agent can tell apart at a glance.

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?

"No account access, no signing" establishes a scope boundary that separates this from account and order tools, so the agent knows this is the read-only market surface. It stops short of naming explicit alternatives (e.g. "use hl_account for balances"), so it's clear context rather than full when/when-not routing.

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