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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive). The description adds genuinely useful behavioral context beyond that: it routes to a huge tool inventory, provides stable citation URIs, is a single fast call, and works on every tier. 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 long but dense with decision-relevant content: preference rules, examples, alternatives, and coverage scope. It is front-loaded with the most critical guidance ('PREFER OVER WEB SEARCH', 'START HERE'). A little redundancy exists, but every section earns its place.

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 broad routing tool with no output schema, this is remarkably complete. It tells the agent what sources are covered, how to phrase questions, what the response will contain (structured answer with citations), when to step up to alternatives, and which tools are not appropriate substitutes. Nothing essential 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?

Input schema coverage is 100% and all six parameters are documented as aliases of the same natural-language question. The description does not elaborate on parameter syntax or format, but the schema already makes the single-argument contract clear, so the baseline 3 is appropriate.

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 identifies a specific verb and resource: it answers factual questions over authoritative structured data and routes to 5,743 tools. It also distinguishes itself from siblings by explicitly naming alternatives like ask_pipeworx_grounded and deep_research rather than leaving the agent to infer the difference.

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 gives explicit when-to-use guidance ('PREFER OVER WEB SEARCH', 'START HERE for most questions'), lists concrete trigger phrases and examples, and names step-up alternatives with the conditions that should select them. It even addresses the breaking-news edge case.

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