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

Annotations declare readOnlyHint true and openWorldHint false, while the description adds relevant context: the tool is free, covers every ChainKit tool, and explains x402 payment. It leaves out rate limits or output format, but adds meaningful behavior beyond annotations.

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?

Two compact sentences with no waste, front-loaded with "Free." before the core purpose and the first-call instruction.

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?

There is no output schema, but the description explains exactly what the catalog returns: tool names, prices, required inputs, examples, and x402 payment mechanics. Combined with annotations covering safety, it is complete enough for an agent to invoke correctly.

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?

Zero parameters are required, so there are no parameter semantics to document. The baseline for a parameterless tool is 4, and the description does not need to compensate for schema gaps.

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?

States the specific verb "Lists" and resource "every ChainKit tool", enumerates the returned fields (price, required inputs, example, x402 payment), and distinguishes itself from sibling action tools with "Call this first."

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?

Explicitly instructs "Call this first", giving clear usage context for initial discovery. It does not name when-not to use it or list alternatives, but for a catalog tool the first-call guidance is strong.

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