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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, and the description reinforces this with 'free and moves no money', plus the useful caveat that feedback gets no individual reply. It does not describe rate limits or response freshness, keeping it at 4 rather than 5.

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?

Front-loaded with 'FREE:' so the safety/speed signal lands first, and each sentence carries routing information. The final two sentences on /feedback are proportionally large for an unrelated concern, a mild bloat but still actionable guidance.

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?

An output schema exists, so return values need not be explained; the description instead covers the safety profile, the purchase alternatives, and how to give feedback. For a zero-parameter informational tool, nothing an agent needs to call it correctly 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?

Zero parameters, so the schema imposes no semantic burden and the baseline of 4 applies. The description correctly does not waste space inventing parameter details.

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 a specific noun-phrase purpose: what agent-exec sells, what it costs, and where to pay. It is clearly a free catalog/pricing read rather than an executor, which distinguishes it from the `execute` sibling, though the phrasing is marketing-flavored rather than a crisp 'returns the service catalog and pricing'.

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 explicitly says the call is free, moves no money, and names the alternatives for actually buying code execution (`execute` via x402 over MCP, or plain HTTP at the returned URLs). It also routes complaints/questions to POST /feedback. What is missing is an explicit 'call this first to discover pricing before using execute' sequencing cue.

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