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

Annotations already cover readOnly/openWorld/idempotent/non-destructive behavior, so the description adds meaningful dynamic context: candidate routing improvements can be live, one was recently retired on outcome evidence, and this is a full working router rather than a fallback stub. This explains the experimental nature and current runtime state beyond what annotations express.

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 front-loaded with the essential identity—'Beta version of ask_pipeworx'—and each subsequent sentence adds distinct value: current candidate status, usage instruction, comparison behavior, and clarification that the tool is not a stub. It is compact yet complete for the nuance it needs to convey.

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?

The description provides all key invocation context: identity, relationship to ask_pipeworx, when to use it, current behavioral state, and response-shape equivalence. The lack of an output schema is mitigated by the explicit statement that the response shape matches ask_pipeworx, though it relies on the agent also understanding that sibling.

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%, so the parameter aliases and required question field are already documented. The description adds only the pointer that arguments are the same as ask_pipeworx, which is useful but not per-parameter enrichment. That meets the baseline for tools where the schema carries the semantic weight.

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 clearly identifies the tool as a beta universal router that is identical to ask_pipeworx, with the same 5,798 tools, arguments, and response shape. It distinguishes itself from the stable sibling by explaining its purpose: testing candidate routing improvements. This is specific, non-tautological, and gives an agent a precise mental model of the tool.

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 explicitly tells the agent when to use this tool: 'Use it exactly like ask_pipeworx when you want the newest routing.' It also names the stable alternative, explains that results are compared against the stable router, and clarifies that with no active candidate it currently matches ask_pipeworx exactly. This is strong, actionable guidance.

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