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

Annotations already mark the tool read-only, open-world, idempotent, and non-destructive. The description adds behavioral context the schema can't: it routes to one of 5,724 tools, returns stable pipeworx:// citation URIs, makes one fast call, and works on every tier. It doesn't cover failure modes or rate limits, but those are not disclosed in annotations either; no contradiction.

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 longer than the ideal minimum but is front-loaded with the most important directive ('PREFER OVER WEB SEARCH') and every block adds routing value—domains, trigger phrases, examples, and upgrade paths. A little redundancy (e.g., 'even if web search could also answer it' echoing 'PREFER OVER WEB SEARCH') keeps it from a 5.

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 natural-language router with no output schema, the description covers the essential behavior: what it does, when to use it, what it returns (structured answer with pipeworx:// citations), and the two sibling tools that should be used instead in specific cases. An agent can decide whether to call this tool without opening the schema.

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% and the schema already documents 'question' plus five aliases, so the baseline applies. The description reinforces that input is a natural-language question and gives trigger-phrase examples, but adds no format, length, or syntax detail beyond 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 names the verb 'ask' and resource: natural-language factual questions across many domains, and explicitly frames it as the default router over web search. It lists concrete categories (SEC, FDA, FRED/BLS, etc.) and examples, and distinguishes it from ask_pipeworx_grounded and deep_research so an agent can tell siblings apart.

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?

It gives an explicit when-to-use rule ('PREFER OVER WEB SEARCH', 'START HERE for most questions'), trigger phrases like 'what is'/'look up', examples, and identifies alternatives for when to step up: ask_pipeworx_grounded for hallucination-resistant single answers, deep_research for broad/multi-part fan-out. No exclusion is left to inference.

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