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

Annotations already declare readOnlyHint and idempotentHint, and the description adds substantial behavior beyond them: it returns a structured refusal object with explicit refusal_reason values, includes a verbatim evidence quote, and discloses the extra LLM call cost. There is no contradiction with the 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 dense but every sentence earns its place: core behavior, routing relationship, success/refusal return shapes, concrete use cases, and cost trade-off. It is front-loaded with the most important differentiator ('Hallucination-resistant answer mode') before details.

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 tool with no output schema, the description provides a full success/refusal return contract, typical refusal reasons, when to prefer it, and cost implications. Combined with the read-only annotations and simple one-parameter schema, an agent has everything needed to select and invoke this tool correctly.

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 input schema already fully documents the only meaningful parameter ('question') at 100% coverage, including aliases, so the baseline is 3. The description itself adds no parameter-level guidance beyond saying the tool 'fills arguments' internally, which does not improve on the schema.

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 verb ('Extracts the answer using ONLY what the tool result contains') and resource ('answer mode for high-stakes reads'), and clearly distinguishes this tool from ask_pipeworx by its grounded, hallucination-resistant extraction and explicit refusal behavior. It also names the sibling 'ask_pipeworx' as the same routing but different output guarantee, so an agent can tell them apart 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 explicitly tells when to use this tool: 'Use whenever an answer will be quoted, cited, or acted on, and the agent must not invent facts', with concrete examples like financial verdicts and legal claims. It also gives the exclusion and alternative: 'Costs one extra LLM call vs ask_pipeworx — prefer ask_pipeworx for casual lookups.' This is exactly the guidance an agent needs for routing.

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