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

The description aligns with the readOnlyHint and goes beyond annotations by specifying that no payment is required, the exact data returned, and the follow-up action to purchase. It adds concrete behavioral context (returns specific fields, triggers a purchase only if the agent chooses to call the endpoint) without contradicting any annotation.

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 two sentences with zero redundancy. The purpose is front-loaded in the first sentence, and the second sentence gives a clear call-to-action for purchase. Every word contributes meaning.

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 parameterless tool with no output schema, the description fully covers what the tool does, what it returns, and the next step to buy. No critical information is missing for an agent to decide whether to invoke it and what to expect from the response.

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 tool has zero parameters, so parameter semantics are trivially satisfied. The description conveys the fixed nature of the offer (endpoint, price, network) without needing parameter documentation, meeting the baseline for a parameterless tool.

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 uses a specific verb 'Inspect' with a specific resource 'exact paid-service offer' and enumerates the exact return fields (endpoint, price, network, asset, receiver). It clearly distinguishes this inspection tool from a purchasing action and provides enough specificity that an agent can understand what it does without opening schemas.

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 implies usage as a pre-purchase inspection step by saying 'without paying' and then directing the agent to call the returned endpoint to buy. However, it does not explicitly differentiate from sibling tools like mars_free_commercial_intelligence_preview or mars_micro_commercial_intelligence_offer, nor does it state when not to use this tool. Guidance is implied rather than explicit.

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