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

Annotations already declare readOnly/idempotent/non-destructive/openWorld, so the safety profile is covered. The description adds genuinely useful non-schema context: a candidate prompt (v9-eval-disjoint-examples) is live on every call, results are compared against the stable router to decide merges, and it is a full working router with no degradation — clarifying this is not a fallback stub.

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?

Front-loaded with the core differentiator (beta, live candidate routing) in the first clause. Mostly tight, though 'Falls back to nothing — this IS a full working router, just the experimental edge' is slightly emphatic/redundant with the earlier 'identical ... full working router' claim.

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?

No output schema exists, and the description compensates by asserting 'same response shape' as ask_pipeworx plus the routing-comparison behavior; all 8 parameters are schema-documented and annotations carry the safety profile. The only gap is that the response shape is defined by reference rather than described here.

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% — the seven aliases (q, ask, text, input, query, prompt, message) and the required 'question' are fully documented in the schema, so the baseline is 3. The description only says 'same arguments' as ask_pipeworx and adds no syntax or format detail beyond the schema.

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+resource (universal router / ask_pipeworx beta) and immediately differentiates from the sibling: 'identical universal router ... with candidate routing improvements enabled live'. An agent can tell it apart 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 an explicit selection condition: 'Use it exactly like ask_pipeworx when you want the newest routing', implying the stable router is the choice when you don't. It stops short of naming when-not/alternatives beyond ask_pipeworx (e.g. ask_pipeworx_grounded), so it is strong but not exhaustive.

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