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

Annotations already establish readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds facts annotations cannot carry: the tool is unavailable, it is priced at 29 USD/month for 3 pairs or 79 USD unlimited via USDC on x402, and invoking it is a no-op status check rather than a subscription action. That is meaningful context beyond the structured fields, though it omits what the status payload contains.

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?

One sentence, front-loaded with the single most decision-relevant fact ('COMING SOON') before any pricing or capability detail. Nothing is redundant with the title. The pricing parenthetical is dense but earns its place, since cost is the main reason an agent would skip this tool.

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 zero-parameter, read-only stub with no output schema, the description covers the three things an agent needs: this is not yet functional, what it will eventually do, and what a call returns today. There is no complexity left unaddressed.

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?

The input schema has zero parameters, which is the baseline-4 case; there is nothing for the description to disambiguate. The description is consistent with that — no behavior implies hidden arguments such as a threshold value or webhook URL.

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 states what the tool is meant to do (push a webhook when a net funding gap or a cost crosses a user-set threshold) and, critically, what it does today (returns its status plus the free tool to use in the meantime). That is specific and distinguishes it from siblings like funding_rates or trading_cost, which return data rather than notify. It loses a point because the active behavior is described only loosely — 'returns its status' — and no specific free tool is named.

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?

It tells the agent it can call this now and that the response will point at a free alternative, which is genuine usage context. But it never names that alternative among the 14 siblings (best_venue, trading_cost, funding_rates would be the obvious candidates), and it gives no explicit when-not-to-use guidance. The guidance is implied rather than actionable.

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