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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false. The description adds materially beyond those: it discloses the extra LLM call cost, the refusal mechanism with the exact refusal_reason enum, and the guarantee that answers are extracted only from tool results. No contradiction with 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?

The description is compact yet information-dense, front-loading the core purpose before mechanics, return contract, usage, and tradeoff. Every sentence earns its place, and the structured flow helps an agent parse it quickly. No fluff or repetition of schema content.

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 supplies the full return shape ({answer, evidence, confidence, source, fetched_at, refusal_reason:null}) and all refusal reasons. It also covers cost tradeoff and selection criteria, so nothing essential to calling the tool 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?

Schema description coverage is 100%: the single semantic parameter `question` is fully documented, and all aliases (q, text, input, query, prompt) are listed in the schema. The description adds no parameter-level meaning beyond what the schema already provides, so the baseline of 3 applies.

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 specific verb+resource ('Hallucination-resistant answer mode for high-stakes reads') and clearly explains the pipeline: route, fill arguments, fetch data, then extract the answer using only tool results. Explicitly contrasts with ask_pipeworx ('Same routing... then EXTRACTS... ONLY what the tool result contains'), so an agent can distinguish it from siblings without opening the 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 guidance ('Use whenever an answer will be quoted, cited, or acted on, and the agent must not invent facts') and when-not-to-use/preference ('prefer ask_pipeworx for casual lookups'), naming the alternative tool directly. This is unambiguous routing guidance.

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