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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the safety profile is covered. The description adds non-obvious operational context beyond that: v0.5 is SDK-only and the test lifecycle uses manual promote/rollback, telling the agent this call does not auto-promote the winner. It still says nothing about side effects on live traffic or what state the test enters.

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?

Two short sentences, front-loaded with the action and prerequisite, with the version caveat appended. No filler or repetition.

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 six-parameter mutation tool with no output schema, it covers purpose, prerequisite, and the manual lifecycle model, and the schema handles all parameter detail. It could go further by pointing to get_production_test for monitoring or naming promote/rollback tools directly, but nothing essential is missing.

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% and every parameter (variantId default winner, customerId superadmin-only, scoreDefinition enum, trafficAllocation, variantPercentage) is documented in the schema itself. The description adds no syntax, defaults, or constraints beyond it, so 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?

States a specific verb and resource ('Start a production A/B test') plus a prerequisite ('for a completed optimization'), which separates it from simulate_ab_test and start_model_test at a glance. It never names those siblings explicitly, so differentiation relies on inference.

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 prerequisite 'for a completed optimization' implies when the tool is applicable, and the v0.5 note hints that promotion is a separate manual step. But it gives no explicit when-not guidance or routing to simulate_ab_test for pre-production testing, so usage is only implied.

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