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

Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds nothing beyond that: it does not mention required inputs, whether variants/weights must be balanced, or what happens on duplicate names. With annotations present the bar is lower, but there is still zero added behavioral context.

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?

The single sentence is front-loaded and wastes no words, but for a mutation tool with four required parameters it is under-specified rather than truly concise. Brevity here comes at the cost of useful context.

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?

This is a write operation with four required parameters, no output schema, and no annotations detail beyond the safety hints. The description says nothing about required fields, weight defaults, or the returned experiment identifier, leaving real gaps for an agent invoking it.

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%, so all five parameters (including the required project, name, variants, goal_event) are documented in the schema with examples for weights and variants. The description adds no syntax, defaults, or constraint information beyond that, so baseline 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 ('Create' + 'A/B experiment'), which is unambiguous. It does not differentiate from siblings such as create_project or update_experiment, but the verb+resource pairing is distinctive enough to identify the operation.

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?

There is no when-to-use guidance, no prerequisites, and no mention of alternatives (e.g., update_experiment for existing experiments). The agent must infer everything from the tool name.

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