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

With no annotations present, the description carries the full burden and does disclose two operationally critical facts: per-call metered cost ($0.02 USDC or credits) and that payment credentials travel in MCP headers (X-Payment / X-Payment-Tx / Bearer token), not in arguments. It does not cover rate limits, latency, or error/auth-failure behavior, so it stops short of top marks.

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 content is front-loaded with the natural-language framing question and the report inventory, which is good, but the definition is bilingual and largely duplicates itself across the zh and en sections (symbol required / Args: symbol restated three times). The core payload is one dense, punctuation-heavy line that is harder to parse than necessary.

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 single-parameter, no-output-schema tool, the description effectively serves as the return-value spec by enumerating every field the report returns, and it covers payment/auth mechanics. The remaining gap is symbol formatting, which an agent needs before it can call the tool reliably.

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 0% and the single parameter is undocumented there, so the description must compensate; it states symbol is required (redundant with the schema) but never specifies the expected format, e.g. BTCUSDT vs BTC vs BTC-USDT, which materially affects call correctness. It does add real value by clarifying that payment headers do not belong in the parameter object.

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 the concrete resource and scope: open interest, 24h OI change, long/short account ratio, long/short share and taker buy/sell ratio across Binance, OKX and Bybit, plus Bybit last price and funding rate. The word "full" hints this is the heavy version of the family, but the sibling perp-positioning.oi_snapshot is never named, so the boundary must be inferred.

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?

Usage is implied by the framing question "how are perpetual traders positioned — full" and by the explicit enumeration of everything the report contains, which lets an agent judge fit. There is no explicit when-to-use versus perp-positioning.oi_snapshot, and no stated exclusions or prerequisites beyond the required symbol.

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