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

Annotations already cover read-only/idempotent/non-destructive/open-world, and the description adds substantial context beyond them: the live experimental behavior (candidate routing may be enabled at any time), the current state (last candidate retired 2026-07-26, so behavior currently matches stable), and the telemetry/feedback loop (results compared against the stable router to decide merges). It also explicitly counters a likely misreading with 'Falls back to nothing — this IS a full working router.' 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?

Four sentences, each earning its place: identity, current runtime status, usage guidance, and a caveat preventing a 'fallback/stub' misreading. It is front-loaded with the defining beta relationship and wastes no words.

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 tool is low-complexity (single free-text question, all aliases schema-documented) with a rich annotation set, so the description's burden is light. It covers identity, current state, when to prefer it, and the return contract ('same response shape') relative to the documented sibling. No output schema exists, but the reference to ask_pipeworx's response shape is sufficient for an agent choosing between the two routing tools.

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% — all six parameters (question plus five aliases) are fully documented in the schema, so the baseline of 3 applies. The description only says 'same arguments' relative to ask_pipeworx, which confirms the parameter surface but adds no per-parameter meaning beyond what the schema already provides.

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 verb+resource: it is a 'universal router' over 5,798 tools, and the beta variant of ask_pipeworx. It precisely distinguishes itself from the sibling ask_pipeworx ('identical... with candidate routing improvements enabled live'), so an agent can tell them apart without opening schemas. Even the current runtime state (no candidate active, matches ask_pipeworx exactly) is spelled out.

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 gives explicit guidance: 'Use it exactly like ask_pipeworx when you want the newest routing' and explains that results are compared against the stable router to decide merges. It names the alternative and the selection condition clearly, but does not state an explicit when-not condition (e.g., 'use ask_pipeworx when you want proven stable routing'), so the exclusion is implied rather than stated.

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