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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, so the description's additional behavioral context is a bonus: it discloses that the tool routes requests to a curated network of thousands of sources, fills arguments automatically, returns citations, and is fast ('one fast call'). These behaviors go beyond the structured annotation hints and give the agent a clear mental model of what will happen when invoked. 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 on the longer side but front-loads the critical directive ('PREFER OVER WEB SEARCH'), then packs in domains, trigger phrases, examples, and routing guidance. Every sentence adds practical value, though there is some redundancy (e.g., repeating that web search could also answer it). The ALL CAPS keywords and clear 'START HERE' / 'Step up only when needed' structure make it scannable. It earns a 4 for density and structure despite minor repetition.

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 complex router tool with no output schema, the description covers the essential contextual elements: what it returns (structured answer with pipeworx:// citation URIs), when to use it, when not to, which siblings to consider, and its operational characteristics (works on every tier, one fast call, covers news). It also provides enough examples to disambiguate the question style. The description is complete for an agent to select and invoke the tool correctly in most scenarios.

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%, with all parameters documented as aliases for the natural-language 'question' parameter. The description adds value beyond the schema by specifying what kinds of questions to submit (trigger phrases, domains, real-world entities/events/numbers) and giving six concrete examples. This enriches the parameter semantics beyond the schema's generic 'Your question or request in natural language.' A 4 is justified because the schema already fully documents parameter names, and the description supplements, not replaces, that documentation.

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 uses a specific verb+resource: 'Routes the question to the right one of 5,908 tools across 1540 verified sources... returns the structured answer with stable pipeworx:// citation URIs.' It clearly identifies the tool as a question-answering router for authoritative structured data and distinguishes itself from siblings by naming ask_pipeworx_grounded and deep_research. The scope is unambiguous and memorable.

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 is explicit about when to prefer this tool over web search, listing domains (SEC filings, FDA, FRED/BLS, patents, real estate, weather, etc.), trigger phrases ('what is', 'look up', 'find', 'get the latest', 'how much', 'current'), and concrete examples. It also explicitly states when to step up to alternatives: 'for a hallucination-resistant single answer... use ask_pipeworx_grounded; for a broad/multi-part question... use deep_research' and clarifies that news is handled by this tool. No guidance 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.