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

With no annotations present the description carries the entire burden and does so unusually well: it declares read-only behavior, a per-execution price ($0.001) with the billing source (daily tariff quota or USD balance), and a precise error contract (JSON error object with syntax correction guidance). Those are the cost and failure-mode facts an agent cannot get from the schema.

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?

Front-loaded and sectioned (BEHAVIOR / PRICING / ACTIONS & RETURNS / USAGE / ERRORS), so the read-only and cost facts appear before the detail. Every block carries information an agent needs given there is no output schema; nothing is redundant 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 9-parameter, 3-mode tool with no output schema and no annotations, the description compensates fully: it explains each action's return fields, the cost model, the error format, and the polling anti-pattern. An agent can select an action and interpret the response without further documentation.

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%, so the baseline is 3; the description adds value by tying each action value to its output shape (screener's symbol/rvol/fund/oi field list, consensus's TA score set, bct_matrix's compact matrices) and by flagging that malformed filter expressions fail with corrective guidance. It does not add syntax detail for tf, limit, columns, exchange, or inline_indicators 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?

Opens with a specific verb+resource ("fetches real-time derivatives intelligence across Binance, Bybit, and Hyperliquid") and then enumerates all three actions with what each returns, so an agent knows exactly which mode to request. It also separates itself from the sibling alert_manager by name.

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?

Gives an explicit positive case ("analyze market state or find trade setups") and an explicit exclusion ("Do NOT use this tool to continuously poll for price updates or wait for conditions") plus the named alternative (alert_manager). That is the full when/when-not/alternative triad.

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