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

Annotations already declare readOnlyHint=true and openWorldHint=false; the description adds the 100-item cap and the idempotent recovery behavior, which are genuinely useful behavioral details. There is no contradiction between the description and 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?

A single, action-first sentence with no wasted words. It efficiently conveys both usage modes and the result cap, making it easy to parse quickly.

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 simple one-optional-parameter read-only tool, the description covers the core behaviors well. However, there is no output schema, and the description does not indicate the shape of returned data, what 'recent' means, or behavior when the idempotency key is not found.

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 only defines idempotency_key as a string, and schema description coverage is 0%. The description adds meaning by connecting the key to recovering the original purchase, but it does not explicitly state that omitting the key triggers the list mode or explain where the key comes from.

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 action ('List'/'recover') and a resource ('jobs'/'purchase'), and adds a clear limit of 100 recent jobs. However, it does not explicitly distinguish this tool from the similar sibling list_buyer_jobs, and the title's 'purchases' vs description's 'jobs' introduces slight terminology 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 two branches—list recent jobs versus recover the original purchase using the idempotency key—imply when the optional parameter should be used. However, there are no explicit conditions, exclusions, or comparison to alternatives, so an agent cannot tell when this tool should be preferred over list_buyer_jobs or get_account_job.

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