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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety bar is low. The description adds substantive context beyond that: there is no fallback to a different tool, this is a fully functional router, and its outputs feed an A/B comparison against the stable router. It doesn't cover rate limits or latency characteristics.

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?

Scope and the key 'matches ask_pipeworx right now' fact are front-loaded, which is good. But the text repeats itself ('identical... same arguments, same response shape' then 'this currently matches ask_pipeworx exactly') and the closing 'Falls back to nothing — this IS a full working router, just the experimental edge' restates an idea already conveyed.

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 read-only router with a fully documented schema and no output schema requirement, the description covers the essentials: what it routes over, how it relates to the stable sibling, and the current no-candidate state. The only gap is that it never mentions the packs parameter, which materially changes routing scope.

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%, with every alias and the packs parameter fully documented in-schema, including the ignored-slug and full-catalog fallback behavior. The description adds no parameter-level detail (notably silent on packs), so the baseline of 3 applies.

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?

States a specific verb and resource (universal router over 7,044 tools) and explicitly distinguishes itself from the sibling ask_pipeworx by saying it is the experimental edge with candidate routing improvements. An agent can tell exactly what it does and how it differs from ask_pipeworx and ask_pipeworx_grounded without opening any schema.

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?

Gives clear selection context: 'use it exactly like ask_pipeworx when you want the newest routing' and notes that results are compared against the stable router. It also discloses that no candidate is currently active, so it matches ask_pipeworx exactly, which is effectively a when-not-necessary signal. It stops short of an explicit 'prefer the stable router for production' directive.

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