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

With no annotations, the description fully carries the behavioral burden. It discloses the paid nature, the payment methods (x402, TCX credits, SOON holder), and explicitly states that unpaid calls return live PAYMENT-REQUIRED accepts. This is strong transparency about the gating behavior, though it doesn't mention rate limits or response shape for paid calls.

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 information-dense but efficient, front-loading the price and endpoint before diving into payment details. Each sentence adds distinct value (cost, default body, payment flow). It's not overly long given the complexity, though it could be tightened by removing redundant payment phrasing.

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 tool with 5 params, no output schema, and no annotations, the description is reasonably complete on the payment side but leaves a gap: what does a successful (paid) call return? It only describes the unpaid response ('PAYMENT-REQUIRED accepts'). The agent cannot anticipate the actual data structure or error handling for paid calls, which is a notable omission for such a transactional tool.

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 schema already documents all 5 parameters with 100% coverage, so baseline is 3. The description adds meaningful context by explaining the default body, the paymentSignature omission behavior (returning a structured challenge), and the meaning of creditsWallet/soonHolderWallet. This goes beyond the schema's terse descriptions and aids correct invocation.

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 is a paid yield-intel service with a specific endpoint and default body, distinguishing it from generic siblings like intel_macro or intel_meteora by focusing on yields and payment mechanics. It avoids tautology and gives concrete details (price, route). However, it does not explicitly define what 'yields' returns beyond payment-required accepts, leaving some ambiguity.

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 never tells the agent when to choose this tool over the many intel_* siblings. It explains the payment flow but not the use case (e.g., 'use when you need cross-protocol yield data'). No exclusions or alternative routing are provided, so the agent must infer from the name and default body.

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