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

Annotations already cover the safety profile (readOnly, idempotent, openWorld), so the description adds genuinely non-redundant behavioral context: routing behavior may change live when a candidate is under test, the exact retirement date of the last candidate, that results feed merge decisions, and the emphatic clarification that 'this IS a full working router,' not a stub. This dynamic-behavior disclosure is exactly what an agent needs beyond the static hints.

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?

Three sentences, front-loaded with the core identity ('Beta version of ask_pipeworx: identical universal router') before state and usage. Each sentence earns its place — identity, current state, usage, and the fallback clarification — though the parenthetical '(same 5,798 tools, same arguments, same response shape)' is slightly redundant after 'identical'.

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 with no output schema, the description covers the critical operational facts: equivalence to the stable version, current experimental state, the dynamic testing behavior, and the reassurance that it is fully functional. The one gap is the concrete response format, which is only referenced indirectly via 'same response shape' and 'use it exactly like ask_pipeworx' rather than described.

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 already documented in the schema. The description only adds 'same arguments' as ask_pipeworx, which is a parity confirmation but adds no new semantic detail, so the baseline 3 is appropriate.

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 identifies the tool as a 'universal router' over 5,798 tools with 'the same arguments, same response shape' as ask_pipeworx, giving a concrete verb+resource+scope. It explicitly distinguishes itself from the stable ask_pipeworx sibling by its experimental 'candidate routing improvements' edge, so an agent can tell them apart without opening either 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?

The description gives an explicit selection condition: 'Use it exactly like ask_pipeworx when you want the newest routing,' and clarifies the current state (no active candidate, matches ask_pipeworx exactly). It does not explicitly state when not to use it or prefer the stable alternative, though the beta framing and 'results are compared against the stable router' imply it.

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