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

Annotations already carry readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable behavioral context beyond those annotations: it routes across 5,724 verified sources, returns structured answers with citation URIs, works on every tier, and is described as 'one fast call'. There is 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 every sentence earns its place: it front-loads the core preference, names the source categories, gives concrete examples, states when to start, and explicitly routes to alternatives. The structure is dense without being redundant, and important guidance like 'START HERE' and 'Step up only when needed' is clearly visible.

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 natural-language routing tool with only one required parameter and no output schema, the description is complete: it explains the input style, the routing behavior, the output format with citation URIs, and the alternatives for other query shapes. It also covers edge cases like breaking news and multi-part research queries. No critical invocation detail 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%, and the single required parameter is well documented as a natural-language question with multiple accepted aliases. The description reinforces that the tool takes free-form factual questions, and examples are already present in the schema, so the description does not need to add more. Baseline 3 applies because the schema carries the parameter-semantics burden.

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 clear verb-resource pair: it 'routes the question to the right one of 5,724 tools' and 'returns the structured answer with stable pipeworx:// citation URIs.' It explicitly distinguishes itself from siblings like ask_pipeworx_grounded and deep_research, and gives concrete examples of questions it handles. An agent can immediately tell what this tool does and why it exists.

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', and 'Use whenever the user asks...'. It also provides when-not-to-use guidance by naming ask_pipeworx_grounded for hallucination-resistant single answers and deep_research for broad/multi-part fan-out. This leaves little ambiguity about tool selection.

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