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

Annotations already declare readOnlyHint/destructiveHint=false, and the description reinforces this with 'This read never purchases or reruns a job.' Beyond that it discloses non-obvious semantics: an empty result does not prove a timed-out submission was rejected, and callers must preserve the original key and inputs on retry. That is exactly the kind of idempotency/retry context annotations cannot carry.

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?

Five short sentences, front-loaded with the tool's dual purpose before the routing and retry caveats. Nothing is wasted, though the omit-vs-supply-key instruction is stated twice (once in the description, once in the schema) and the follow-up-tool sentence could be trimmed.

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 zero-required-param, single-key read with an output schema, this covers purpose, alternatives, parameter modes, follow-up tool for status/result/receipt, and the critical retry-safety caveat. An agent has everything needed to call it correctly and interpret an empty 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?

Schema coverage is 100% and the single parameter is fully documented there, so the baseline is 3. The description goes further by framing the parameter as a mode switch (omit for history vs. pass the exact original key to recover one uncertain purchase) and by warning against minting a replacement key, which adds intent the schema alone only states as a rule.

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 a concrete verb (list/find) and resource (this agent's recent jobs / account-funded purchase) and explicitly scopes it as 'for this agent'. It differentiates itself from list_buyer_jobs, search_buyer_jobs, and get_account_job by name and by role, so an agent can select it without opening a schema.

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?

Gives explicit when-to-use ('purchase history and recovery before retrying an uncertain submission'), explicit alternatives ('use list_buyer_jobs or search_buyer_jobs for available services'), and a follow-up route ('Use a returned job ID with get_account_job'). It also tells the caller which parameter mode selects which behavior, so nothing is left to inference.

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