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

The annotations already indicate read-only (readOnlyHint: true) and open-world behavior. The description adds specific behavioral details: pairs not listed on a given exchange are marked failed without failing other exchanges, and symbols are auto-mapped from Binance format. These are valuable non-obvious behaviors that enhance transparency.

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 description is a single, front-loaded sentence that packs in the action (compare), the metrics (funding rate, last price, OI, 24h change), the exchanges, the purpose, and the handling of unlisted pairs. No redundancy, every phrase earns its place—ideal for an MCP description.

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 the tool's complexity (multi-exchange, mapping, failure handling) and lack of an output schema, the description covers all critical aspects: what metrics are compared, which exchanges, symbol format, and per-exchange failure isolation. It doesn't mention return format, but that's not expected without an output schema. Slight room for improvement by noting potential limitations like availability of data for all exchanges.

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%, but the description adds meaning by clarifying that the symbol must be in Binance Futures format (e.g., BTCUSDT) and that it is auto-mapped to other exchanges. This goes beyond the schema's basic 'Binance USDS-M Futures perpetual' constraint, helping the agent understand the mapping behavior.

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 clearly states the tool's function: comparing funding rate, last price, OI, and 24h change for one pair across four exchanges (Binance/Bybit/OKX/Hyperliquid). It also states the specific purpose—detecting funding divergence and seeing leverage accumulation—which differentiates it from single-exchange siblings like binance_get_funding_rate or binance_scan_funding_extremes.

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 implicitly makes the use case clear: it's for cross-exchange comparison, while siblings focus on single-exchange data. It does not explicitly name alternatives or exclusions, but the emphasis on 'across exchanges' and the auto-mapped symbol format provides clear contextual guidance. A explicit 'when to use' statement would push it to 5.

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