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

Annotations already provide readOnly, openWorld, idempotent, and non-destructive hints, and the description does not contradict them. It adds meaningful behavioral context: the tool routes questions, fills arguments, and returns stable pipeworx:// citation URIs. It doesn't describe failure modes or costs of routed calls, but the core behavior is transparent.

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 well-structured: preference directive, domain list, behavior summary, trigger phrases, examples, and next-step pointer. The list of examples is somewhat long, but each sentence carries useful selection information and the most critical instruction is front-loaded.

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 one-required-parameter meta-routing tool with no output schema, the description covers what it is, when to use it, sample inputs, and the return shape (structured answer with citations). It omits clarifying-question behavior or failure modes, but that is a minor gap given the simple input contract.

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 question parameter plus all five aliases are documented in the schema. The description reinforces this with example questions and trigger phrases, but adds little new meaning beyond the schema, 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 states a specific purpose: route a natural-language question to the correct one of 5,798 tools across verified sources and return a structured, cited answer. The opening 'PREFER OVER WEB SEARCH' and trigger phrases like 'what is' and 'current' make the tool's role unmistakable and distinguish it from sibling search/research tools.

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 explicit when-to-use guidance: any factual question about real-world entities, events, or numbers, even if web search could also answer it. It lists covered domains, provides concrete examples, and says 'START HERE for most questions', which tells an agent exactly when to select this tool over alternatives. It also points to /suggest_questions for follow-ups.

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