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

Annotations already declare readOnly/idempotent/openWorld/non-destructive, so the safety profile is covered. The description adds real value beyond that: the upstream source (Hyperliquid HIP-4), the per-call price ($0.005), the sort order (most traded first), and the returned fields. It stops short of stating freshness/latency or pagination behavior.

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 dense but well-ordered sentence: source and cost first, then row shape and sort order, then filtering. No filler sentences and nothing redundant.

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?

There is no output schema, so the description carries the burden of describing return values, and it does so concretely (question, per-option probability, 24h change in points, 24h USDC volume, sort order) plus the data source. Nothing essential for correct invocation 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%, so the enum values, default limit, and max are already documented in the schema; baseline is 3. The description's 'filter by category or text' merely restates the two filters without adding syntax, matching rules, or edge cases beyond 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?

Specific verb+resource: it lists live prediction markets from a named source (Hyperliquid HIP-4) and describes the exact shape of each row (question, option probabilities, 24h point change, 24h USDC volume, sorted by volume). An agent can distinguish it from neighbors like macro.fed_odds or market.opportunities 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 closing 'Filter by category or text' implies how to narrow results, but there is no explicit when-to-use guidance, no when-not, and no routing to or away from adjacent siblings such as macro.fed_odds (Fed odds) or market.opportunities. Usage is implied rather than stated.

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