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

Annotations declare readOnly and openWorld, but the description adds materially useful context beyond them: latency ('under a minute'), a paid-per-call model (0.28 USDC via x402 at a specific endpoint), and a tracked-protocols-only constraint. This goes well past what the annotations convey, though the identity/wallet boilerplate dilutes it.

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 metric enumeration is front-loaded and earns its place, but the tail end balloons with ERC-8004/Virtuals identity verification, two URLs, and a payout wallet address that add little to the invocation decision. Payment info is relevant; the verified-identity block is bloat.

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 paid, read-only, single-param tool with no output schema, the description covers the returned fields, coverage limits, latency, and payment mechanics. An agent has enough to decide and invoke correctly; only explicit sibling routing 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 coverage is 100% and already documents 'DefiLlama protocol name or slug'. The description adds a concrete example ({"protocol":"aave"}) and reinforces the slug/name convention, which is marginal value over the schema. Baseline 3 is appropriate for full-coverage single-param tools.

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: returns a DeFi protocol health snapshot, and enumerates exactly what it contains (TVL with 1d/7d/30d change, fees/revenue, fees/TVL, revenue share, mcap/revenue, past hacks). This clearly delimits it from research-oriented siblings, though it never names base_protocol_health or another alternative to sharpen the distinction.

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?

Provides an input example and a coverage constraint ('Only protocols DefiLlama tracks'), which implies when it applies. But there is no explicit when-to-use/when-not guidance relative to siblings like base_protocol_health or token_due_diligence, so the agent must infer the routing.

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