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

Goes well past the annotations (readOnlyHint=false, openWorldHint=true) by disclosing the async job model, 24-hour turnaround, the polling endpoint, pricing (0.25 USDC or a pack credit), and refund behavior for failed calls under both payment modes. This is exactly the non-obvious operational context an agent needs before spending money.

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 what the tool produces and its async nature, then cost and billing caveats in the right order. The billing/refund sentences are long conditional chains but each carries information an agent would otherwise have to guess.

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?

With no output schema, the description compensates fully by enumerating the finished brief's fields (title, summary, markdown body, source links, word count) and explaining how to retrieve them for free. Turnaround, cost, and failure semantics are all covered.

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%, so both parameters are already documented. The description restates the 500 default and 50-1500 range for max_words and adds that at least 3 public web sources are cited, which is mild added value rather than new syntax or constraint detail.

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 first sentence names a specific deliverable (a cited research brief) and immediately flags the async, made-to-order nature. It never names the closest sibling, deep_brief, so an agent cannot tell from this text alone which of the two to pick.

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?

Usage is implied through workflow: submit, get a job id and due time, then poll GET /v1/jobs/:id. But there is no explicit when-to-use/when-not guidance and no routing to alternatives like deep_brief or brief_status, which are directly relevant siblings.

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